This breakfast casserole recipe is perfect for feeding a crowd. Filled with potatoes and veggies, it's hearty, delicious, and easy to make ahead!
A breakfast casserole is the best way to feed a crowd first thing in the morning. Just ask my mom! She’s been making her famous breakfast casserole recipe on Easter and Christmas morning for as long as I can remember. The rest of my family loves it because it’s hearty and flavorful, packed with potatoes, veggies, eggs, and cheese. My mom loves it because it’s easy to make and—even better—make ahead. She can prep the whole thing the night before and pop it in the oven when guests arrive the next day.
I adapted this breakfast casserole recipe from hers, and it checks all the same boxes.
- You can make it ahead.
- It’s simple to throw together.
- It’s satisfying and delicious.
- And you can adapt it to use different cheeses or vegetables.
We love this recipe, and I hope you do as well! It’s perfect for special occasions, but it’s so tasty that you might want it in your regular breakfast rotation too.
What’s In This Easy Breakfast Casserole
This breakfast casserole recipe has 4 main parts:
- Potatoes – Roasted with olive oil, salt, and pepper, they create a starchy, satisfying layer at the bottom of the casserole. I like to use Yukon Gold potatoes here because I love their creamy texture, but russet potatoes work too.
- Sautéed veggies – Yellow onion, garlic, peppers, spinach, and green onions add vibrant color and savory flavor to the casserole.
- Cheddar cheese – It adds richness and salty, nutty flavor. I layer some into the casserole and sprinkle more on top.
- The egg mixture – I whisk the eggs with milk so that they have a delicate, fluffy texture when baked. Use any type of unsweetened milk you like. I’ve successfully made this recipe with whole milk and unsweetened almond milk many times.
Find the complete recipe with measurements below.
Recipe Variations
Like my frittata recipe or crustless quiche, this breakfast casserole is adaptable! Here are a few ways to change it up:
- Vary the veggies. Sautéed broccoli, mushrooms, asparagus, or zucchini would be a nice alternative to the peppers and/or spinach.
- Change the cheese. Pepper jack cheese is a fun replacement for the shredded cheddar. A mix of cheeses works too!
- Switch to sweet potatoes. They’re just as good as regular ones in this hearty breakfast casserole.
How to Make This Breakfast Casserole
This breakfast casserole recipe is easy to make! You can find the complete recipe with measurements at the bottom of this post, but for now, here’s an overview of how it goes:
First, roast the potatoes. Chop them into 1/4-inch cubes. Note: This is small! Smaller cubes=more crisp, golden brown edges. Be careful not to cut them too large.
Place the chopped potatoes on a parchment-lined baking sheet, and toss them with olive oil, salt, and pepper. Roast at 425°F for 20 to 25 minutes, or until tender and browned.
Meanwhile, prep the egg mixture. Whisk together the eggs, milk, and 1/4 teaspoon salt in a large bowl. Set aside.
Next, cook the veggies. Sauté the onion until soft, and then add the peppers and garlic. Cook for 2 minutes before adding the spinach and half the green onions. Cook until the spinach is just wilted.
Then, assemble the casserole. Spread the roasted potatoes at the bottom of an oiled 9×13-inch baking dish. Top with two-thirds of the cheese, followed by the sautéed veggies.
Pour in the egg mixture. Finally, sprinkle the remaining cheese and reserved green onions on top.
Bake the casserole at 350°F until the eggs are set, 40 to 45 minutes. Let stand for 5 minutes before slicing and serving. Enjoy!
Make-Ahead Breakfast Casserole
One of my favorite things about this egg casserole recipe is that you can make it ahead. No need to get up at the crack of dawn in order to have it ready in time for brunch!
Here are two options for prepping it in advance:
- Assemble the casserole the night before. Like a french toast casserole, this breakfast casserole can be assembled a day ahead. Layer the potatoes, vegetables, cheese, and egg mixture in the pan, and tightly cover with foil or plastic wrap. Refrigerate overnight. The next morning, uncover and let sit at room temperature while you preheat the oven. Then, bake according to the recipe.
- Cook the components the day before and assemble in the morning. Roast the potatoes and sauté the veggies a day ahead, and store them in airtight containers in the fridge. With these components prepped, the egg casserole is quick and easy to assemble day-of.
Storing and Reheating Leftovers
If you have leftover breakfast casserole, you’re in luck. It reheats perfectly! Store slices in an airtight container in the fridge for up to 3 days, and warm them in the microwave before serving.
You can also freeze this breakfast casserole. Wrap slices tightly in foil or plastic wrap, or seal them in an airtight container. Freeze for up to 3 months. Allow to thaw overnight in the fridge before reheating.
What to Serve with Breakfast Casserole
This easy make-ahead breakfast casserole recipe is flavorful and filling, so you don’t need to pair it with much more than fresh fruit for a satisfying breakfast.
That said, it’s a wonderful addition to a larger brunch. Try pairing it with any of these recipes:
Looking for more brunch ideas? Check out these 51 Best Brunch Recipes!
Breakfast Casserole
Equipment
Ingredients
For the potatoes
- 3 Yukon Gold potatoes, about 1 pound, chopped into ¼-inch pieces
- 1 tablespoon extra-virgin olive oil
- ½ teaspoon sea salt
- Freshly ground black pepper
For the casserole
- 12 large eggs
- 1 cup milk, any kind
- 1¼ teaspoons sea salt
- 2 tablespoons extra-virgin olive oil, plus more for the baking dish
- ½ medium yellow onion, chopped
- Freshly ground black pepper
- 2 garlic cloves, chopped
- 1 red bell pepper, stemmed, seeded, and chopped
- 1 green bell pepper, stemmed, seeded, and chopped
- 1 cup fresh spinach, roughly chopped
- 4 green onions, chopped
- 1½ cups shredded cheddar cheese
Instructions
- Roast the potatoes: Preheat the oven to 425°F and line a baking sheet with parchment paper. Place the potatoes on the baking sheet. Drizzle with the olive oil and sprinkle with the salt and several grinds of pepper. Toss to coat. Spread evenly on the baking sheet and roast for 20 to 25 minutes, or until tender and browned.
- Make the casserole: Reduce the oven temperature to 350°F and oil a 9x13-inch baking dish.
- In a large bowl, whisk together the eggs, milk, and ¼ teaspoon of the salt. Set aside.
- Heat the olive oil in a large skillet over medium heat. Add the onion, the remaining 1 teaspoon salt, and several grinds of pepper. Cook, stirring occasionally, for 5 to 8 minutes, or until soft. Add the garlic, red pepper, and green pepper and cook, stirring occasionally, for 2 minutes. Add the spinach and half the green onions and toss until the spinach is just wilted.
- Spread the potatoes in an even layer in the prepared baking dish. Top with 1 cup of the cheese, followed by the sautéed veggies. Pour in the egg mixture and sprinkle with the remaining ½ cup cheese and the reserved green onions.
- Bake for 40 to 45 minutes, or until the eggs are set.
- Let stand for 5 minutes before slicing and serving.
Made this for a church potluck. Made the night before and reheated in the oven at church and it was totally delicious! None was left.
Med issues so can’t do any shopping for potatoes for a few days. I do have instant mashed potatoes that I could make and layer for the base. Any thoughts?
Really enjoyed making this. I put pepper jack cheese for extra heat and finely chopped kale instead of spinach. I also roasted the cubed potatoes right in my 9×13 glass dish. I was generous with the olive oil so I didn’t regrease the pan, I just scraped off any crusty potato bits before adding the other components. Turned out great and so far is releasing easily from the pan.
This recipe works perfectly every time! Thankyou for a delicious and impressive breakfast idea. I made individual portions in muffin cups and that worked great as well.
Me again… How many does “batch” yeild? It looks like 12 for a 9×13 dish – however your photo looks like it is 8, What is a realistic portion out of a a 9×12 dish?
Hi Jennifer, I typically slice this into 12. With sides, that’s a great portion. If you’re serving it on its own, you may want to do 8.
Hi. This looks great!!! I am going to be making 8 of these casseroles for a church function. I want to make 4 vegetable (as you have listed) and 4 meat. Do you have any recommendations on what kind of meat to use? Sausage crumbles? How much would you say?
I am trying to make it not as difficult as possible, so would frozen hash browns/shredded potatoes work?
Thank you so much!
Hi Jennifer, we’ve never made this recipe with meat so I’m not sure about the quantity, but I think you could definitely added cooked sausage or bacon. I think the frozen potatoes would work too. I’d thaw them and pat them dry before adding them to the baking dish.
My dish is bigger, 15 x 10 ( 4.8 qt – 4.5 l). So I’m planning on using 14 eggs, more vegetables and more milk.
How long should I bake it?
Hi Maggie, I would check it at the same time the recipe has listed and just test the middle to make sure it’s done. It’s hard to say exactly without trying.
Can you add cottage cheese to this and if so how much would you recommend. I’d like to add more protein.
Hi Nellie, I haven’t tried this but I think you could probably replace the 1 cup of milk with 1 cup cottage cheese. Or you could try these egg bites instead: https://www.loveandlemons.com/egg-bites-recipe/
Made this for Father’s Day. Everyone loved it!
I gave some to my neighbor who took it into work for breakfast. She put it in the microwave and people started poking their head’s out of their offices asking, “What is that?!
She swears she could have sold a couple of squares right then and there!
Ha ha, I’m so glad everyone loved it!
Can I half this receipt with 6 eggs and bake in an 8.5×8.5 baking dish?
Thank you
Hi Lee, we haven’t tried it, so I can’t say for sure, but I think it would work fine!
I am adding pork sausage to one and turkey sausage to another plus extra vegetables. I will send pictures when I am done.
Hi Barbara, I hope you enjoyed the casseroles!
Crowd favourite!
Hi Kayla, so glad it was a hit!
This looks so good. I have a guest with a huge aversion to bell peppers. Any idea what to substitute with?
Hi Michelle, small broccoli florets, chopped asparagus, carrots, or mushrooms would all be great here – it’s a flexible recipe!
Great suggestions!! Thanks
Can you prepare (not cook) this recipe, freeze, and then thaw the night before and cook the next morning?
Hi Alyssa, it might work, but we haven’t tried it so I can’t say for sure.
Yummy casserole for Easter brunch. I used 4 packed cups of spinach instead of the one in recipe. Next time I will repeat 4 cups & even increase. Spinach wilts down into almost nothing!
Hi Eva, I’m always a fan of extra veggies in a recipe! So glad you enjoyed the casserole.
Can indiv. servings be frozen for x amount of time successfully?
Hi, yes! You can wrap individual servings in foil or seal them in an airtight container and freeze for up to 3 months. I’d let them thaw overnight in the fridge before reheating in the microwave or oven.
I’ve made this recipe twice in the past two weeks and it’s a new staple in my house! The first time I followed the recipe exactly (minus the green bell pepper). The second time, I swapped out the red pepper for mushrooms. Amazing both times! Also, I swear this tastes better reheated in the oven the next day. Thank you!
Hi Meghan, Amazing! So glad you love the recipe, and thanks for sharing your variations!
The casserole recipe sounds absolutely delicious and perfect for a crowd! I love how it’s packed with hearty ingredients like roasted potatoes, veggies, eggs, and cheese. Plus, the make-ahead options make it super convenient for busy mornings or special occasions. Can’t wait to give it a try and impress my guests!
Hi, I hope you enjoy!
Looks delish! Can this be made ahead? (Like a strata?) Thank you!
Oh gosh! I didn’t read the entire article – just jumped to the recipe! I DO see how to make ahead! Thanks!
this was soo good
i omitted green onions and added chopped broccoli
my daughter who hates veggies but loves eggs asked for second
Hi Carly, so glad it was a hit!