Easy Breakfast Casserole Recipe From Scratch

I make this breakfast casserole at least twice a month and it never fails. Getting eggs, cheese, and sausage to come together in a single baking dish sounds simple, but most recipes end up either rubbery or bland. This easy breakfast casserole recipe uses pantry staples, takes 10 minutes to assemble, and feeds a crowd without any stress.

Why This Breakfast Casserole Works

The secret is the egg-to-milk ratio. Too much milk and the casserole stays wet and loose in the center. I use 8 eggs to ¾ cup whole milk — enough to set firm but stay custardy and tender, not dry.

Browning the sausage first removes excess grease and builds a deeper savory base. Skipping this step is why so many breakfast casseroles taste flat. That fond at the bottom of the pan goes straight into the egg mixture.

Day-old bread soaks up the custard without going mushy. Fresh bread releases too much moisture and makes the bottom layer soggy. I keep a bag of cubed bread in the freezer specifically for this recipe.

Ingredients

• 8 large eggs
• ¾ cup whole milk
• 1 pound breakfast sausage, casings removed
• 3 cups day-old bread, cubed (about ½-inch pieces)
• 1½ cups shredded sharp cheddar cheese, divided
• ½ cup diced yellow onion
• ½ cup diced green bell pepper
• 1 teaspoon garlic powder
• ½ teaspoon smoked paprika
• ½ teaspoon salt
• ¼ teaspoon black pepper
• 1 tablespoon butter, for greasing

What You Need for Breakfast Casserole

Eggs — the structural base. Large eggs give the most consistent set. Extra-large eggs add too much moisture.

Whole milk — adds creaminess without making the casserole loose. Skim milk produces a rubbery texture.

Breakfast sausage — pork sausage gives the most flavor. Italian sausage works as a swap — remove the casings and crumble it the same way.

Day-old bread — sourdough, white sandwich bread, or French bread all work. The drier the better — it absorbs the custard without collapsing.

Sharp cheddar — the sharpness cuts through the richness of the eggs and sausage. Mild cheddar gets lost. Gruyère is a great swap for a more refined version.

Smoked paprika — adds a subtle depth that makes the casserole taste like it took hours. Regular paprika works but lacks the smokiness.

How to Make Breakfast Casserole

1. Preheat your oven to 375°F. Grease a 9×13-inch baking dish with butter.
2. Heat a large skillet over medium-high heat. Add the breakfast sausage and break it into crumbles. Cook for 6–8 minutes until browned. Drain excess grease.
3. Add the diced onion and green bell pepper to the same skillet. Cook for 3 minutes until softened. Remove from heat.
4. Spread the cubed bread evenly across the bottom of the greased baking dish.
5. Scatter the sausage and vegetable mixture over the bread. Top with 1 cup of the shredded cheddar.
6. In a large bowl, whisk together the eggs, whole milk, garlic powder, smoked paprika, salt, and black pepper until fully combined.
7. Pour the egg mixture evenly over the bread and sausage layer. Press down gently with a spatula so the bread soaks up the custard.
8. Sprinkle the remaining ½ cup of cheddar over the top.
9. Bake uncovered at 375°F for 40–45 minutes until the center is set and the top is golden brown. A knife inserted in the center should come out clean.
10. Let the casserole rest for 5 minutes before slicing and serving.

Breakfast Casserole Variations

Vegetable Breakfast Casserole

Skip the sausage and double the vegetables. Add diced mushrooms, baby spinach, and cherry tomatoes to the skillet with the onion and pepper. The mushrooms release moisture as they cook — let them go a full 5 minutes until that liquid evaporates before adding to the baking dish.

Ham and Cheese Breakfast Casserole

Swap the sausage for 1½ cups of diced cooked ham. No browning needed — just scatter it over the bread layer. Swiss cheese instead of cheddar pairs especially well with ham and gives the top a nutty golden crust.

Spicy Breakfast Casserole

Use hot breakfast sausage and add ½ teaspoon of crushed red pepper flakes to the egg mixture. A handful of pickled jalapeños layered over the sausage before pouring the custard adds a bright vinegary heat that cuts through the richness.

Overnight Breakfast Casserole

Assemble the entire casserole the night before, cover tightly with plastic wrap, and refrigerate for 8–12 hours. The bread fully absorbs the custard overnight. Pull it from the fridge 20 minutes before baking and add 5 minutes to the bake time since it starts cold.

Gluten-Free Breakfast Casserole

Replace the bread with cubed gluten-free sandwich bread or frozen hashbrown potatoes (thawed and patted dry). The hashbrown version creates a crispy base layer that holds up well under the egg and sausage filling.

Tips for the Best Breakfast Casserole

• I always use day-old bread — fresh bread releases moisture and makes the bottom layer soggy.
• Brown the sausage until you see real color on the crumbles — pale sausage adds fat but no flavor.
• Press the bread down after pouring the egg mixture so every cube gets soaked through.
• Reserve that top half cup of cheese and add it in the last 10 minutes if you want a deeper golden crust.
• Let it rest 5 minutes before cutting — the center continues setting as it sits.
• For clean slices, run a thin spatula along the edges and corners before scooping out the first piece.

Make Ahead & Storage

This breakfast casserole keeps in the fridge for up to 4 days covered tightly. I slice it into individual portions before storing so reheating is faster. A single slice takes 90 seconds in the microwave or 10 minutes in a 325°F oven.

To freeze, let the baked casserole cool completely. Slice into portions, wrap each in plastic wrap, then foil, and freeze for up to 2 months. Thaw overnight in the fridge and reheat in the oven at 325°F for 15 minutes. The texture holds well — the bread stays tender and the eggs do not turn rubbery.

Common Questions

Can I make breakfast casserole the night before?

Yes. Assemble it completely, cover with plastic wrap, and refrigerate overnight. The bread absorbs the custard fully which actually improves the texture. Add 5 minutes to the bake time since it goes into the oven cold.

How do I know when breakfast casserole is done?

Insert a thin knife or toothpick into the center — it should come out clean with no wet egg mixture clinging to it. The edges will be set and golden before the center is fully done, so always test the middle.

Can I freeze breakfast casserole?

Yes. Bake it fully, let it cool, then slice and freeze individual portions wrapped in foil. Reheat from frozen at 325°F for 20–25 minutes or thaw overnight and reheat for 15 minutes.

What bread works best for breakfast casserole?

Day-old sourdough, French bread, or white sandwich bread all work well. The key is that the bread is slightly dry so it absorbs the custard rather than releasing extra moisture. Brioche adds richness but can make the bottom too dense.

Can I use turkey sausage instead of pork?

Yes. Turkey sausage works — brown it the same way. It has less fat so the crumbles stay leaner and the overall casserole is lighter. Add a drizzle of olive oil to the skillet so the turkey sausage does not stick.

This easy breakfast casserole recipe is the one I reach for every holiday morning and busy weekend. Save this recipe and come back to it every time you need to feed a group without standing over the stove.