Healthy Breakfast Casserole

You occasionally need a wholesome breakfast that you can prepare ahead of time. This breakfast casserole is perfect if you’re feeding a large group of people or attempting to make busy workday mornings a little easier.

Sausage and potatoes are typically included in breakfast casseroles. Instead, I stuffed this one full of fresh vegetables and greens including spinach, red bell pepper, and green onion.

A creamy feta or goat cheese completes the dish. The wonderful, opulent texture may be achieved without using a lot of dairy. This recipe has been lightened up, but it tastes more decadent than it actually is.

The ideal addition to a holiday meal buffet is this nutritious breakfast casserole. It’s a terrific method to help balance those yummy carb-heavy delights, like muffins and pancakes, because it delivers some protein and vegetables. If this was available together with cream cheese and bagels, I would be happy. Lunch is a wonderful time to eat leftovers.

I used my failsafe frittata formula to create this recipe. It’s simple to prepare, attractive, and delicious!

Breakfast Casserole Recipe

The complete recipe can be seen below, but here is a quick summary:

When the bell peppers, green onion, and garlic are soft, add the spinach and cook until it has wilted. In order to prevent the warm vegetables from cooking the eggs when we stir them together, set the pan aside for a few minutes to cool.
Salt and pepper are added to the eggs along with a small amount of full-fat dairy, such as whole milk or Greek yogurt. Add half of the cheese; the remaining cheese will be used to top the dish.
Add the vegetables to the egg mixture, stir to blend, and then carefully spoon the mixture into a baking dish that has been buttered. Finish with the remaining cheese.
Bake until the eggs are cooked through. That’s it!

How to Prepare This Casserole in Advance

Prepare the mixture as specified, then chill the egg and veggie mixture in a mixing basin or in the prepared baking dish for up to two days.

Bake as advised, understanding that your dish may require a few more minutes in the oven as it’s starting off cold (particularly if you refrigerated in the baking dish) (especially if you refrigerated in the baking dish).

Also read: Blender Oatmeal Pancakes


  • 1 tablespoon extra-virgin olive oil
  • 2 medium red bell peppers, diced (approximately 2 cups) (about 2 cups)
  • ¾ cup thinly sliced green onion (approximately 1 small bunch) (about 1 small bunch)
  • 5 ounces coarsely chopped spinach (approximately 5 cups) (about 5 cups)
  • 12 eggs
  • 3 tablespoons full-fat dairy (heavy cream, half-and-half, whole milk, sour cream or yogurt) (heavy cream, half-and-half, whole milk, sour cream or yogurt)
  • Several dashes of your favorite hot sauce, like Cholula
  • 12 teaspoon of salt, fine
  • 10 twists of freshly ground black pepper
  • 4 ounces (1 cup) (1 cup) crumbled feta or goat cheese


  1. Set the oven’s temperature 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).
  2. In a large skillet, preheat the olive oil over medium heat until shimmering. Add the bell pepper and green onion and simmer until the pepper is soft and cooked through, about 8 to 10 minutes.
  3. Add the spinach to the skillet and simmer, while stirring, until wilted, about 2 minutes. Set the pan aside to cool for a bit while we create the egg mixture.
  4. Crack the eggs into a medium mixing basin. Add your dairy of choice, several dashes of spicy sauce, plus the salt and pepper. Whisk just until the egg yolks and whites are mixed.
  5. Stir in half of the cheese (we’re keeping the other half for topping the frittata before baking). Transfer the lightly cooled veggies into the bowl, and toss to incorporate.
  6. Pour the ingredients into the prepared pan. Evenly scatter the remaining cheese on top.
  7. Bake for 25 to 35 minutes (keep an eye on it), until the eggs are puffy and appear cooked, and the center of the frittata just barely jiggles when you give it a little shimmy. For good measure, stab a fork about ¼-inch into the center of the eggs and make sure the fork comes out clean.
  8. Place the frittata on a cooling rack until you’re ready to serve. Slice with a sharp knife, and serve. Leftovers will store nicely for about four days in the refrigerator. Enjoy leftovers cold, at room temperature, or gently reheat in the microwave or oven.


PREPARE IN ADVANCE: Cover and refrigerate the ingredients until you’re ready to bake (it should keep nicely for up to two days) (it should keep well for up to two days). Bake as suggested, but note that your dish may require a few extra minutes in the oven as it’s starting off chilly.

CHANGE IT UP: I love the tastes you see here, but you can easily use different vegetables in similar quantities. More tough greens like kale or chard will require a bit more cooking time. Find other taste variations in my frittata article.

CAN I FREEZE IT? I don’t advocate freezing leftover breakfast casserole. When I defrosted my frozen slices, they got quite liquid and bit rubbery. If you’re searching for a fantastic egg-based freezer dish, check out my breakfast burritos.