Fluffy High-Protein Cottage Cheese Breakfast Casserole

This cottage cheese breakfast casserole is a quick, protein-packed start to the day that keeps you full for hours. It comes together in one bowl and bakes into a golden, custard-like slice.

The cottage cheese melts into the eggs, so every bite is tender, not spongy. Prepare it ahead on a Sunday and reheat squares all week.

Why This Casserole Works

The cottage cheese does two things: it packs each slice with serious protein, and it keeps the bake remarkably moist the next day. I’ve never pulled a dried-out piece out of the fridge.

I also love that the base stays the same while the mix-ins shift to whatever vegetables or leftover meat are in the fridge. It’s the kind of recipe that actually earns its place in a weekly rotation.

Ingredients

• 6 large eggs: room temperature eggs blend more easily, but cold eggs still work.
• 1 cup cottage cheese: full-fat gives the creamiest texture, but low-fat is fine.
• 1 cup shredded sharp cheddar cheese: sharp cheddar keeps the flavor from getting lost; pre-shredded works in a pinch.
• 1/2 cup milk: any dairy or unsweetened non-dairy milk works here.
• 1/4 cup all-purpose flour: helps bind the casserole without making it heavy; almond flour works for a gluten-free version.
• 1/2 tsp baking powder: gives a little lift so the eggs don’t turn dense.
• 1/2 tsp salt: table salt or fine sea salt.
• 1/4 tsp black pepper
• 1 cup packed baby spinach, chopped: fresh spinach wilts right into the bake; no need to cook it first.
• 1/2 cup diced bell pepper: any color; red or orange add a subtle sweetness.
• 1/4 cup diced yellow onion
• 1/2 cup cooked turkey sausage, crumbled: optional, or use diced ham or crumbled bacon.

Variations / Substitutions

• Make It Vegetarian: skip the sausage and toss in 1/2 cup sautéed mushrooms or an extra handful of bell pepper. The bake still holds together perfectly.
• Dairy-Free Option: swap the cottage cheese for a thick dairy-free yogurt and use a dairy-free shredded cheese; the texture will be slightly softer but still satisfying.
• Herb and Spice Boost: add 1/2 tsp smoked paprika or a pinch of crushed red pepper with the dry ingredients.
• Switch Up the Greens: try finely chopped kale or thawed, squeezed-dry frozen spinach instead of fresh spinach.

If you enjoy this, you might also like my Spinach and Feta Egg Bake.

How to Make Cottage Cheese Breakfast Casserole

Step 1: Whisk the Eggs and Cottage Cheese

Preheat the oven to 375°F (190°C) and grease a 9-inch square baking dish. In a large bowl, whisk the 6 eggs, 1 cup cottage cheese, 1/2 cup milk, 1/2 tsp salt, and 1/4 tsp pepper until smooth.

The cottage cheese will leave small curds no matter how long you whisk, and that’s exactly what you want. They melt down during baking, creating little pockets of creaminess.

Step 2: Stir in the Binders and Cheese

Sprinkle the 1/4 cup flour and 1/2 tsp baking powder over the egg mixture. Whisk until just combined, then fold in the 1 cup shredded cheddar.

The batter will look quite thin at this stage. That thinness is normal, the flour and cheese settle into a tender custard as it bakes.

Step 3: Fold in the Vegetables and Meat

Add the 1 cup chopped spinach, 1/2 cup diced bell pepper, 1/4 cup diced onion, and the cooked sausage if you’re using it. Fold gently until everything is evenly distributed.

The spinach might seem like a lot, but it wilts down in the oven. Resist the urge to squeeze it, the moisture it releases steams the casserole slightly and prevents it from drying out.

Step 4: Bake the Casserole

Pour the whole mixture into the greased dish and spread it flat. Bake on the center rack for 35 to 40 minutes, or until the top is puffed and deeply golden and the center barely jiggles when you give the dish a little shake.

A knife inserted near the middle should come out mostly clean. Let the dish rest on a cooling rack for 5 minutes, it’ll finish setting and cut into much cleaner squares.

Step 5: Slice and Serve

Cut the casserole into 6 even squares and lift them out with a spatula. The top shatters just a bit where the cheese browned, and the inside stays soft and creamy.

Serve them warm as is, or add a dollop of sour cream and a few dashes of hot sauce for a tangy finish.

A Few Tips for the Fluffiest Casserole

• For a deeper, crunchier top, switch the oven to broil for the last 2 minutes of baking. Watch it closely so the cheese doesn’t burn.
• The casserole will puff up quite a bit in the oven, don’t be alarmed. It settles as it cools, leaving a tender, not deflated, texture.
• Check your baking powder before you start. If it’s been sitting opened for months, the casserole won’t get the same gentle rise.

Bake times by pan size:

Storing Leftover Casserole

• Refrigerate: keep slices in an airtight container for up to 4 days.
• Reheating: microwave individual squares for 1 to 2 minutes, or warm them in a 350°F oven for 10 minutes.
• Serve Cold: the slices are thick and custardy, so they’re actually delicious eaten straight from the fridge with a shake of extra salt.

What to Serve With Cottage Cheese Breakfast Casserole

A handful of peppery arugula tossed with lemon juice and olive oil cuts right through the richness of the eggs and cheese. Fresh berries or a simple fruit salad add a bright, sweet contrast. For a little heat, serve the squares with a spoonful of salsa or a drizzle of hot sauce.

Frequently Asked Questions

Can I assemble this the night before?

Yes. Mix everything, pour it into the baking dish, cover, and refrigerate overnight. In the morning, bake straight from the fridge and add 5 to 10 extra minutes to the bake time.

Can I freeze the baked casserole?

Absolutely. Wrap individual cooled squares tightly and freeze for up to 2 months. Reheat in the microwave or oven without thawing first.

What can I use instead of cottage cheese?

Ricotta is the closest swap and gives a slightly finer, less curdy texture. Mascarpone works but tastes richer; drain some of the liquid if using it.

Why did my casserole turn out watery?

The most common reason is using frozen spinach that hasn’t been thoroughly squeezed dry. Stick to the amounts of fresh vegetables listed, since they release just the right amount of moisture as they cook.

Cottage Cheese Breakfast Casserole Recipe

Print Recipe Pin Recipe

Prep Time 10 minutes mins

Cook Time 35 minutes mins

Total Time 45 minutes mins

Servings: 6 servings

Calories: 220

Ingredients Method Notes

Ingredients

  

• 6 large eggs
• 1 cup cottage cheese
• 1 cup shredded sharp cheddar cheese
• 1/2 cup milk
• 1/4 cup all-purpose flour
• 1/2 tsp baking powder
• 1/2 tsp salt
• 1/4 tsp black pepper
• 1 cup packed baby spinach, chopped
• 1/2 cup diced bell pepper
• 1/4 cup diced yellow onion
• 1/2 cup cooked turkey sausage, crumbled (optional)

Method

 

1. Preheat oven to 375°F (190°C) and grease a 9-inch square baking dish.
2. In a large bowl, whisk together eggs, cottage cheese, milk, salt, and pepper until smooth. Whisk in flour and baking powder, then stir in cheddar.
3. Fold in spinach, bell pepper, onion, and sausage (if using) until evenly mixed. Pour the batter into the prepared dish.
4. Bake 35 to 40 minutes, until puffed, golden, and the center feels set with a slight jiggle. Let cool 5 minutes before slicing.
5. Slice into squares and serve warm.

Notes

For a make-ahead option, assemble the unbaked casserole, cover, and refrigerate overnight. Bake straight from the fridge the next morning, adding 5 to 10 minutes to the time listed.