Name: High Protein Egg Casserole
Prep time: 15 min
Cook time: 45 min
Total time: 1 h
Yield: 8 servings
Cuisine: American
Ingredients: 12 large eggs; 1 1/2 cups cottage cheese; 2 cups shredded cheddar cheese; 1 pound cooked breakfast sausage, diced; 1 cup diced bell peppers; 1/2 cup diced onion; 1 cup chopped spinach; 1 tsp garlic powder; 1/2 tsp smoked paprika; 1 tsp salt; 1/2 tsp black pepper; 1 tbsp olive oil for sautéing; nonstick cooking spray for greasing

Table of Contents

Why You’ll Love This Recipe
Ingredients You’ll Need
Tips for the Best Results
Storage and Reheating
Frequently Asked Questions

High Protein Egg Casserole

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If you’ve ever stood in front of the fridge at 7am with zero motivation to cook breakfast, this casserole is your answer. It’s basically a giant frittata’s more laid-back cousin — you mix everything in one bowl, pour it into a dish, and let the oven do the rest. Whether you’re meal-prepping for the week or feeding a hungry table on a Sunday morning, this one earns its spot in the regular rotation.

Why You’ll Love This Recipe

This casserole packs in a serious amount of protein without tasting like “diet food.” Eggs, cottage cheese, and a generous handful of cheese give it that rich, custardy texture while keeping you full for hours.

It’s also wonderfully low-effort. There’s no sautéing in batches or babysitting a pan — you whisk, pour, add your mix-ins, and bake. Cleanup is basically just one bowl and one dish.

And honestly, it’s flexible in the best way. You can swap in whatever veggies or meat you have on hand, and it still turns out great every single time.

Ingredients You’ll Need

The base of this casserole is eggs, obviously, but the real protein boost comes from cottage cheese blended right into the egg mixture. Don’t worry if you’re not usually a cottage cheese fan — once it’s blended smooth, you won’t even notice the texture, just a creamier, richer bake.

Shredded cheese is non-negotiable here for me. A sharp cheddar or a Mexican blend melts beautifully and gives the top that golden, slightly crispy edge that makes everyone go back for seconds.

For protein and flavor, diced cooked turkey sausage, breakfast sausage, or even diced ham works great. If you want to keep things vegetarian, black beans or extra cheese can fill that gap just fine.

Veggies are where you can really make this your own. Bell peppers, spinach, onions, and mushrooms all hold up well in the oven and add color and freshness. Just make sure anything with high water content, like spinach or mushrooms, gets a quick sauté first so your casserole doesn’t turn watery.

A little salt, pepper, garlic powder, and a pinch of smoked paprika round out the seasoning without overcomplicating things.

Tips for the Best Results

💡 Tip: Blend your cottage cheese with a few of the eggs before mixing in the rest. This breaks down the curds so you get a smooth, even texture throughout instead of cottage cheese clumps.

Pre-cook any watery vegetables and let them cool slightly before adding them in. This one step is the difference between a firm, sliceable casserole and a soggy one.

Don’t skip greasing your baking dish well, even if it’s nonstick. Egg casseroles love to stick, and a well-greased dish makes serving so much easier.

Let the casserole rest for about 5-10 minutes after it comes out of the oven. It’ll firm up as it sits, which makes cutting clean slices way easier.

Storage and Reheating

This casserole is honestly even better the next day, which makes it perfect for meal prep. Let it cool completely before storing so it doesn’t get soggy from trapped steam.

Store leftovers in an airtight container in the fridge for up to 4 days. Note: if you’re slicing it into individual portions for the week, separate them with parchment paper so they don’t stick together.

For reheating, the microwave is your friend for a quick single serving — about 60-90 seconds usually does it. If you want to bring back that slightly crisp top, pop a slice in the oven or toaster oven at 350°F for about 10 minutes instead.

You can also freeze individual portions for up to 2 months. Just thaw overnight in the fridge before reheating for the best texture.

Frequently Asked Questions

Can I make this casserole ahead of time?
Yes, you can assemble the whole thing the night before, cover it, and refrigerate it unbaked. In the morning, just pop it straight into the oven, adding a few extra minutes to the bake time since it’ll be starting cold.

Why is my egg casserole watery?
This usually happens when veggies release moisture during baking. Pre-cooking anything with high water content, like mushrooms, zucchini, or spinach, before mixing it in solves this almost every time.

Can I use egg whites instead of whole eggs?
You can substitute some or all of the whole eggs with egg whites to boost the protein content even further. Just know the texture will be a bit lighter and less rich, so you might want to keep a few whole eggs in the mix for flavor.

How do I know when the casserole is done?
The center should be set and just slightly jiggly, not liquid, and a knife inserted in the middle should come out clean. If the top is browning too fast but the center isn’t set, loosely cover it with foil for the remaining bake time.

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