Sometimes, you need a healthy make-ahead breakfast. Whether you’re serving a crowd or trying to ease busy weekday mornings, this breakfast casserole is just the ticket.
Typically, breakfast casseroles includes sausage and potatoes. I loaded this one up with fresh veggies and greens instead, including red bell pepper, green onion and spinach.
Creamy feta or goat cheese rounds it all out. You don’t need a ton of dairy to achieve a lovely, luxurious texture. This is a lightened-up dish that seems more indulgent than it really is.
This healthy breakfast casserole is the perfect addition to a holiday breakfast spread. Since it offers some protein and vegetables, it’s a great way to help balance those delicious carb-heavy treats, like muffins and pancakes. I’d be thrilled to find this option alongside bagels and cream cheese. Leftovers are good for lunch, too.
To develop this recipe, I followed my foolproof frittata formula. It’s easy to make, colorful and delicious!
How to Make Breakfast Casserole
You’ll find the full recipe below, but here’s a brief summary:
- Sauté the bell peppers and green onion until tender, then add spinach and cook until wilted. Set the pan aside for a few minutes to cool, so the warm veggies don’t cook the eggs when we stir them together.
- Whisk together the eggs with a dash of full-fat dairy, like whole milk or Greek yogurt, plus some salt and pepper. Stir in half of the cheese (we’re reserving the other half for topping the casserole).
- Transfer the veggies into the egg mixture, stir to combine, then gently pour it all into a buttered baking dish. Top with the rest of the cheese.
- Bake until the eggs are cooked through. That’s it!
How to Prepare This Casserole in Advance
Prepare the mixture as instructed, but refrigerate the egg and veggie mixture in a mixing bowl or in the buttered baking dish for up to two days.
Bake as directed, knowing that your dish may require a few extra minutes in the oven since it’s starting off cold (especially if you refrigerated in the baking dish).
Breakfast Casserole Serving Suggestions
This breakfast casserole would fit in nicely with any breakfast spread. Here are some general suggestions:
- Avocado Toast or any other toast
- Bagels with cream cheese and toppings
- Crispy Hash Browns, which you can make in a skillet while the frittata cooks
- Muffins, pancakes and waffles
- Salads, for an all-around healthy meal
Please let me know how your breakfast casserole turns out in the comments! I love hearing from you.
Healthy Breakfast Casserole
- Author:
- Prep Time: 10 minutes
- Cook Time: 40 minutes
- Total Time: 50 minutes
- Yield: 8 servings 1x
- Category: Breakfast
- Method: Baked
- Cuisine: American
- Diet: Vegetarian
Make this healthy breakfast casserole recipe for the holidays or busy weekday mornings! Featuring red bell peppers, spinach and creamy cheese, this casserole is wholesome, hearty and full of fresh flavor. Recipe yields 8 generous servings.
Ingredients
- 1 tablespoon extra-virgin olive oil
-
2 medium red bell peppers, chopped (about 2 cups)
-
¾ cup thinly sliced green onion (about 1 small bunch)
-
5 ounces roughly chopped spinach (about 5 cups)
- 12 eggs
-
3 tablespoons full-fat dairy (heavy cream, half-and-half, whole milk, sour cream or yogurt)
-
Several dashes of your favorite hot sauce, like Cholula
-
½ teaspoon fine salt
-
10 twists of freshly ground black pepper
-
4 ounces (1 cup) crumbled feta or goat cheese
Instructions
- Preheat the oven to 350 degrees Fahrenheit. Grease a 9 by 13-inch pan with butter (don’t be tempted to use cooking spray; it doesn’t work nearly as well).
- In a large skillet, warm the olive oil over medium heat until shimmering. Add the bell pepper and green onion and cook until the pepper is tender and cooked through, about 8 to 10 minutes.
- Add the spinach to the skillet and cook, while stirring, until wilted, about 2 minutes. Set the pan aside to cool for a bit while we prepare the egg mixture.
- Crack the eggs into a medium mixing bowl. Add your dairy of choice, several dashes of hot sauce, plus the salt and pepper. Whisk just until the egg yolks and whites are blended.
- Stir in half of the cheese (we’re reserving the other half for topping the frittata before baking). Transfer the lightly cooled veggies into the bowl, and stir to combine.
- Pour the mixture into the prepared pan. Evenly disperse the remaining cheese on top.
- Bake for 25 to 35 minutes (keep an eye on it), until the eggs are puffed and appear cooked, and the center of the frittata just barely jiggles when you give it a gentle shimmy. For good measure, insert a fork about ¼-inch into the center of the eggs and make sure the fork comes out clean
- Place the frittata on a cooling rack until you’re ready to serve. Slice with a sharp knife, and serve. Leftovers will keep well for about four days in the refrigerator. Enjoy leftovers chilled, at room temperature, or gently reheat in the microwave or oven.
Notes
Prepare in advance: Cover and refrigerate the mixture until you’re ready to bake (it should keep well for up to two days). Bake as directed, but know that your dish may require a few extra minutes in the oven since it’s starting off cold.
Change it up: I love the flavors you see here, but you can definitely use other vegetables in similar quantities. More hardy greens like kale or chard will require a bit more cooking time. Find other flavor variations on my frittata post.
Can I freeze it? I don’t recommend freezing leftover breakfast casserole. When I defrosted my frozen slices, they turned very watery and slightly rubbery. If you’re looking for a good egg-based freezer recipe, check out my breakfast burritos.
Vegetable enthusiast. Dog lover. I'm probably making a big mess in my Kansas City kitchen right now. 
Katlyn Smalley
I had never heard of a breakfast casserole before. I am glad I this recipe post, because I am very interested in trying this some time soon.
Heather Thiele
I have a sensitivity to egg yolk, but I can tolerate egg whites. Any suggestions on how to switch up the recipe? Also, I was thinking of adding artichokes for a Mediterranean spin. Thoughts on how much?
Kate
Hi Heather! I haven’t tried this recipe with egg whites only, but I imagine it would work! I think you’d need about 2 egg whites per whole egg. Artichoke sounds nice! I’d try up to 3/4 cup chopped.
Jo Jo
I made this a couple of days ago and it turned out great! I only had one bell pepper and mozzarella cheese instead of feta. I used sour cream as my dairy. Delish and beautiful! I will definitely make again.
★★★★★
Kate
Hooray! Thank you, Jo Jo!
Andrew F
Can’t wait to make this on the weekend! Looks nutritious and delicious.
★★★★★
Kate
Thanks Andrew! Please report back if you try it. :)
Deborah A Wagner
Kate,
I have an a heart transplant so I can’t eat feta (which I love) or goat cheese. What other type of cheese can I add. Will swiss work?
Thanks,
Kate
Hi Deborah, I think Swiss, mozzarella or any melty cheese would be nice. I don’t know the details of your restrictions, but if you’re avoiding unpasteurized cheese, many feta and goat cheese options are pasteurized but would need to be verified on a label-by-label basis. I hope you enjoy this dish!
Donice Gilliland
Kate do you think Gruyere would work for the cheese in the casserole – for those family members who don’t like most other cheeses? (Which can be selectively sprinkled on top!)
Kate
Hi Donice, yes, I think Gruyere would be great!
Katy Mabee
I love a good breakfast casserole! There are so many ways to make this. I’ll even use up veggie scraps in the fridge with a few eggs and make a mini one just for me. Brunch for one! (no showering required.) ;)
★★★★★
Kate
Thanks Katy! I hope you love this one! Yay for brunch in any form. :)
Celia
I subbed cheddar cheese and added broccoli florets since we were a little short on spinach. This was a total hit with the family, the only thing is that it only took 20 min to cook and even then was just slightly overdone. Overall great recipe, would make again!
★★★★
Kate
I’m sorry to hear that! Thank you for your feedback. Sounds like your oven may run hotter than mine, so adjust the timing some next time.
Sylvia W
This sounds lovely! Now that is is finally cool enough to turn the oven on (Florida takes its own sweet time cooling down LOL) I have been thinking breakfast casserole. I made my first one almost by accident, but it rapidly became a lovely habit. I tend to use sweet potato rather than white potatoes in mine, but this lighter veggie version sounds yummy!
Stephanie
Hi! How important is the dairy in the recipe? I’d like to make this for a family where one of the individuals doesn’t eat dairy. Can it be eliminated?
Kate
Hi! I find this ones is best with dairy. Sorry! Maybe try one of How to Make Frittatas (Stovetop or Baked) ideas instead?
Nathalie
I made this for lunch, with a bunch of kale instead of the spinach. It fed 6 (not very hungry) people. A nice make-ahead dish!
As a former student in Bordeaux, France, I am sure you know that une casserole is a French word meaning a pot. How come it became a breakfast frittata in the US I wonder :) ?
★★★★
Kate
Hi Nathalie! Glad to hear it! You know, my French is pretty rusty and I did not remember that! “Casserole” is used to refer to baked dishes of this nature over here. Even lasagna would fall under our definition. Funny how words shift in meaning sometimes.
Debbie
This sounds wonderful! I would like to try it for family that are on a low cholesterol diet. Do you think I can use an egg substiute or even half substitute and half eggs to lower the cholesterol count?
Kate
Hi Debbie, I’m not sure an egg substitute would give you your desired outcome. If you try it, let me know.
Veronica
This is so good! My 2 year old and 6 year old loved it too. Thanks for such a great breakfast!
★★★★★
Kate
Hooray! I’m so glad! Thank you, Veronica.
Megan
Delicious! I followed the recipe as is, except for using shredded colby jack instead of feta because it was what I had on hand. Wholesome, nutritious, and tasty. Yet another “keeper” recipe from you!
★★★★★
Kate
Marvelous! Thank you so much for your review, Megan!
Natasha
Made this tonight for dinner and extremely happy with how it turned out. SO delicious! I also appreciate how simple and nutritious this dish is. I added some mushrooms because we love them and probably over did it a little with the amount of vegetables in general, but it’s a forgiving recipe and didn’t take away from flavor. The colors of veggies make it visually comforting, too :)
Thank you, Kate, for another fantastic recipe!
★★★★★
Kate
Thank you, Natasha! Mushrooms sound like a delicious addition. I’m so glad you’re enjoying this one!
Sarah DeMeola
Pretty good! It was easy to put together and a result everyone likes. I always appreciate having a breakfast option in the fridge that we can eat off of for a few days. It makes the mornings more enjoyable! PS this is toddler approved too! My husband adds extra hot sauce. :)
★★★★
Kate
I’m so glad to hear it, Sarah! Thank you for reporting back. :)
Heather
This casserole is so delicious! I have a love/hate relationship with eggs but loved everything about this dish. I stayed true to your recipe and it is perfect! My husband is a meat eater who doesn’t love goat cheese and even he gave it a 10/10. I’m looking forward to making it again using one of your frittata variations (mushrooms, arugula, and cheese). Yum!
★★★★★
Kate
I’m glad you loved everything about this dish, Heather! Thank you for taking the time to review.
Wendy Eaton
So good! I prepared this the night before, covered the pan and put in the refrigerator. The next morning, I sprinkled the remaining goat cheese on top and baked, concerned the eggs might be a little flat. However, the eggs fluffed up beautifully, and everyone said this recipe is a keeper.
★★★★★
Kate
Thank you, Wendy! I’m so glad to hear it.
John
Wonderful recipe. We don’t like onion but added some sautéed mushrooms in place.
★★★★★
Kate
Thanks John! Your version sounds delicious.
Ashley
5 Stars! I made this for the morning after Thanksgiving (prepared veggies ahead of time) and it was a huge hit! Everyone loved it. We used spinach, tomato, onion, feta and parsley. This morning I made it again and used spinach, onion, garlic, purple potatoes and added rosemary & thyme. SO GOOD. Much appreciation xo
★★★★★
Kate
I’m excited you loved it, Ashely! Thank you for taking the time to review.
Katie Farinas
Hi! Although I love veggies, I have some serious meat eaters in my family. Would this work with crumbed sausage? Could I still make it the night before?
Kate
Hi Katie, I’m not sure, sorry! May need to adjust quantities.
Laura
I’ve made this twice now and each time it’s been wonderful! I make it on the weekend so I don’t have cook breakfast during the week. Delicious and filling!
★★★★★
Mindi Hartman
Made this recipe for lunch yesterday. It was delicious and I would make it again! I loved the directions for making in advance which I did and then it was very simple to combine it and bake when needed. The only thing I found is that it would feed 5-6 people max and definitely not 8 unless you had a few side dishes to go with it. We had ours with light rye and pumpernickel toast. If I had the time, I would have a nice big salad on the side. I used a 9 x 13 pyrex casserole and that was a good choice.
★★★★★
Kate
Wonderful to hear!! Thank you for sharing, Mindi.
Roger| India Today Restaurant
Food always feels like luxury when you’re hungry.
★★★★
Tegan Tingley
This was excellent! We were getting a back log of eggs from our backyard chickens, so this was perfect.
I did 6 eggs instead of 12, but kept most everything else the same or scaled down by 25%. It was delicious!
★★★★★
Kate
Hi Tegan! Thank you for sharing. I’m glad you were able to make it work by scaling down.
Amanda
I just made this for Christmas morning and it’s perfect! It may become an annual holiday tradition. Fabulous recipe, and so easy—but it impresses and satisfies everyone, and the colors are festive. Thank you!
★★★★★
Kate
I love that! This is a great one for that. I appreciate your review, Amanda.
Julie
Yum! Prepped on Christmas Eve and baked on Christmas morning. Turned out perfect. Thanks for a healthy, festive, and delicious recipe.
★★★★★
Kate
Wonderful to hear, Julie! Thank you for your review.
Martha
I made this in advance for our Christmas morning breakfast. I loved it! I loved how easy it was to prepare – hardly any cooking, and so convenient to have ready to stick in the oven in the morning. I left it in the oven a bit too long because I was worried the centre was raw, but it continued to cook after I removed it, so I should have trusted your direction and taken it out when the centre was still jiggly. Will make again for a weekend treat as it was so easy! Thanks Kate!
★★★★★
Kate
A great one to make ahead! Thank you for sharing, Maratha.
Mary
if I only have extra large eggs, should I reduce the number of eggs used in this recipe? What do you suggest?
Kate
Hi! You can use the same amount here, or leave a few out if they are quite large. I can’t say for sure without trying it myself.
Mary D.
A simple recipe that offers lots of flavor. A definite keeper. I used yogurt and crumbled goat cheese from the lists of possibilities, in case others are interested.
★★★★★
Shayla
This is my new favorite Saturday Brunch recipe! Saturdays at our house mean sleeping in a little with the kids, so I loved that I could make it the night before, and just throw it in the next morning. The kids approved too! I used plain Greek yogurt as my dairy and it gave a perfect taste with the feta cheese. Thanks for sharing!
★★★★★
Stephanie Ripley
Do you think this is still good if I make and take to work and warm up in microwave?
Kate
Hi! I have rewarmed it and didn’t mind the results. Just be careful to not over do it! I’m not a fan of overcooked eggs :)
Connie R
So good! Made this recipe for a family brunch and it was a big hit!!
Next time I think I’ll add some tomato, and less feta.
★★★★★
Kate
That’s great, Connie! Thank you for your review.
Kathy
Hi- Can I pre cook this and travel with it to reheat the next day? Or will it be too dried out?
Thank you, sounds delicious.
Kate
Hi! You can have this as leftovers.
Brittney
I’ve made this recipe twice now! The first time I followed the recipe. The second time I switched out the veggies. I used spinach, green pepper, mushrooms, sun-dried tomatoes, and red onion. It is SO GOOD!
I make this casserole on Sunday and then portion it out for the rest of the week. Each morning during the week I pop it in the oven for 10 minutes. It didn’t taste good in the microwave.
Thank you for a delicious meal prep recipe!
★★★★★
Kate
I like that combination with the mushrooms! Thank you for sharing, Brittney.
claudia
I prepared this casserole for brunch and served it with the Vibrant Orange Salad and everyone enjoyed the meal! The casserole comes together easily and it is light not leaving you feeling stuffed. I will be making this again! Thanks Kate!
★★★★★
Carole
Hello! I’m wondering why full fat dairy is specified. I would usually reach for the Skyr in this situation, but that is low in fat. Any reason not to go low fat?
Kate
Hi! I find full fat helps is not become watery and helps the flavor.
AJ
This is so delicious! A simple and delicious go-to breakfast.
★★★★★
Kate
Thank you for your review, AJ!
Debra
Hi Kate,
Yesterday for Mothers Day my daughter and I made your breakfast casserole dish. Fantastic! I just love all the veggie included in this dish and I have to say the feta cheese really brings it over the edge. Thank you for your recipe. Love it!
Kate
Sounds like a fun project to do together! Thank you for sharing, Debra.
Madeline
I made this for Mother’s Day brunch and it was fantastic! Thank you so much!
★★★★★
Kate
You’re welcome! Thank you for sharing, Madeline.
Tracey
I made this recipe last week and it was perfect for daily breakfasts! I wrapped each piece in plastic wrap and placed in the refrigerator but I noticed a bunch of condensation. Any storage tips ? Also, can this recipe be halved? Thanks !
Kate
Hi Tracey! You can keep it in your refrigerator covered. It can be cut in half, just use a smaller baking dish.