This spinach breakfast casserole is perfect for a weekend brunch or weekday breakfast meal prep idea. The combination of eggs, fresh spinach, potatoes, and cheese creates a delicious and nutritious vegetarian meal.

Slice of spinach breakfast casserole on a spatula in a white casserole dish.

If you’ve been through my breakfast recipes, you’ve likely noticed that I’m a big fan of breakfast casseroles. These crustless quiche and frittata-inspired casseroles are a simple and easy way to create a hearty breakfast without much effort – just add everything to a baking dish, bake, and enjoy!

Not only is this spinach breakfast casserole easy to make but it’s incredibly versatile and keeps well in the fridge and freezer. You can make it ahead of time, store it in the fridge, and then reheat it in the morning and enjoy it on its own, with a side of toast, or fresh fruit for a hearty and healthy breakfast.

Slice of spinach breakfast casserole on a white plate with a fork.

Why You’ll Love It

High in Protein – With almost 20 grams of protein per serving, this casserole is a great way to add protein to your breakfast.
Full of Greens – Each serving contains 3/4 cup of spinach to ensure you’re getting your daily dose of leafy greens in each slice.
Well-Balanced – This spinach breakfast casserole is a well-balanced meal with equal amounts of protein, complex carbohydrates, and healthy fats.
Great for Meal Prep – This casserole keeps well in the fridge for days making it a great make-ahead breakfast for weekday mornings.

Ingredients for Spinach Breakfast Casserole

Eggs – A dozen eggs to ensure the casserole is filled with protein and healthy fats.
Spinach – To add some leafy greens and fiber. The recipe calls for fresh spinach, but you can use frozen spinach if preferred. See the notes section of the recipe card for details.
Potatoes – The recipe calls for baby potatoes, since they cook faster, however, you can use large potatoes if needed. See the notes section of the recipe card for details.
Leek – To add flavor. You can use a small onion if preferred.
Cheese – To add some protein and healthy fats. The recipe calls for sharp cheddar cheese, but you can use any shredded cheese you like. Feta cheese would also work well.
Butter and Olive Oil – To sauté the veggies.
Salt and Pepper – To season the egg mixture. If you want to enhance the flavors, you can also add a sprinkle of garlic powder, onion powder, or Italian seasoning.

Sautéd leeks and chopped spinach in a pan.

Dietary Adaptions

To Make it Gluten-Free: No adaptations are needed, this recipe is gluten-free.

To Make it Dairy-Free: Swap the butter for additional olive oil.

To Increase the Protein Content: Add some cooked chopped bacon or sliced breakfast sausage.

To Add More Veggies: Add some diced bell pepper, sliced mushrooms, or green onions. Sauté them with the leek before adding them to the dish.

Cooked baby potatoes in a casserole dish.

Cooked potatoes and spinach mixture in a casserole dish.

How to Make a Breakfast Casserole with Spinach

Boil the potatoes. Bring a pot of well-salted water to a boil, add the baby potatoes, and cook for 10 minutes. Once cooked, cut them into quarters or halves.
Sauté the leek and spinach. In a pan, warm the butter and olive oil, add the diced leek, and sauté for 3-4 minutes until tender, then add the spinach and cook for an additional minute until wilted.
Whisk the eggs. In a large bowl, crack the eggs, add the salt and pepper, and whisk until well combined.
Fill a baking dish. Add the potatoes to the baking dish, top with the leek and spinach mixture, sprinkle with shredded cheese, and pour in the egg mixture.
Bake. Transfer the baking dish to an oven at 400°F and bake for 25-30 minutes or until the eggs are set.
Serve and enjoy!

You can find the detailed instructions in the recipe card below.

Cooked potatoes, spinach mixture, and shredded cheese in a casserole dish.

Egg mixture for breakfast casserole recipe ready for the oven.

How to Meal Prep Breakfast Casserole

Not only is this spinach breakfast casserole easy to make but it perfect for meal prep. Simply prepare the casserole as instructed, allow it to cool completely, then slice it into 6 servings, place them in airtight containers, and store them in the fridge for up to 4 days.

Red’s Nutrition Tip

This spinach egg casserole is a balanced meal with a similar amount of protein, carbohydrates, and fat. To increase the protein content of the meal, serve it with a side of breakfast sausage or Greek yogurt. To increase the carbohydrate and fiber content of the meal, serve it with toast and fresh fruit. To increase the fat content of the meal, serve it with some avocado or additional cheese.

Egg casserole with spinach in a baking dish.

What to Serve with Spinach Breakfast Casserole

This spinach breakfast casserole pairs well with:

Breakfast sausage
Turkey sausage
Bacon
Toast
English muffins
Bagel
Yogurt
Fruit salad
Green salad
Avocado
Sour cream
Cheese
Hot sauce

Slice of egg casserole with spinach on a white plate with a fork.

Storage + Reheating

To Refrigerate: Allow the egg casserole to cool completely, cover the dish with aluminum foil or plastic wrap, or transfer the leftover pieces to an airtight container and store it in the refrigerator for up to 4 days.

To Freeze: Allow the egg casserole to cool completely, then cover it with aluminum foil and plastic wrap or a freezer-safe bag and store it in the freezer for up to 3 months.

To Reheat: To reheat whole, allow the egg casserole to thaw completely or reheat directly from the fridge, uncovered, by baking in the oven at 350°F for 15-20 minutes or until heated through. Individual pieces can be reheated in an oven-proof dish in the oven at 350°F for 5-10 minutes or in a microwave-safe container in the microwave for 1-2 minutes.

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