Breakfast Sausage Casserole

The kitchen was still dark when I started cubing the bread, the house quiet except for the hum of the refrigerator. My cousin's wedding brunch was in six hours, and I'd promised to handle the main dish. That morning, watching sleepy relatives take their first bites and seeing their eyes light up, I understood why this kind of food sticks with people. Something about warm, savory breakfast brings out the best in everyone.

Last Christmas morning, my brother-in-law wandered into the kitchen at 6 AM, smelled the sausage browning, and ended up 'helping' by sampling every single ingredient. We've made it a tradition now—he shows up early, coffee in hand, under the guise of assistance. The casserole disappears faster every year.

Ingredients

• 1 pound breakfast sausage: The foundation of the whole dish, so choose a quality brand you actually enjoy eating on its own
• 8 large eggs: Room temperature eggs incorporate more smoothly into the milk mixture
• 2 cups whole milk: Creates that creamy, custard-like texture that holds everything together
• 6 cups day-old bread cubes: Slightly stale bread absorbs the egg mixture better than fresh, preventing a soggy bottom
• 2 cups shredded cheddar cheese: Sharp cheddar adds that punchy flavor that cuts through the richness
• 1/2 cup shredded mozzarella: Provides the gorgeous golden melt on top
• 1 teaspoon salt and 1/2 teaspoon black pepper: Dont underestimate this—eggs need proper seasoning to shine
• 1/2 teaspoon dried mustard powder: The secret ingredient that makes it taste like brunch, not breakfast
• 1 small yellow onion and 1/2 red bell pepper: Optional but worth it for depth and color

Instructions

Brown your sausage with intention:

Cook the sausage in a large skillet over medium heat, breaking it into small crumbles with your spoon until its deeply browned and cooked through, about 5 to 7 minutes. Toss in the onion and bell pepper now if youre using them, cooking until theyre soft and fragrant. Drain the excess fat but dont wipe the skillet—you want those browned bits to stay right where they are.

Build the foundation:

Spread your bread cubes evenly across a buttered 9x13-inch baking dish. Scatter the cooked sausage mixture over the bread, making sure those savory bits are distributed throughout so every serving gets plenty.

Whisk up the custard:

In a large bowl, beat the eggs with the milk, salt, pepper, mustard powder, and paprika until the mixture is completely uniform and frothy. Stir in 1 1/2 cups of the cheddar and all the mozzarella—the cheese should melt slightly into the warm eggs.

Bring it together:

Pour the egg mixture evenly over the entire dish, then use your hands to gently press the bread down into the liquid. This step matters—the bread needs to be submerged so it can transform into that tender, custard-like texture we're after. Sprinkle the remaining cheddar across the top.

Bake to golden perfection:

Cover tightly with foil and bake at 350°F for 30 minutes, then remove the foil and continue baking for another 15 minutes until the top is golden brown and the center is set when you give it a gentle shake. Let it rest for 10 minutes before serving—this is crucial for clean slices.

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My grandmother used to say that casseroles are just love in a baking dish, and I finally understand what she meant. Theres something about a dish that brings everyone to the table at once, no standing at the stove, no plating individually—just a steaming, cheesy centerpiece that says 'stay awhile'.

Making It Ahead

Assemble everything the night before, cover tightly with foil, and refrigerate. The bread will absorb even more of the custard overnight, resulting in an incredibly creamy texture. Add 10 minutes to the covered baking time if it goes into the oven cold.

Customizing Your Casserole

Swap cheddar for Swiss, pepper jack, or gruyère depending on your mood. Add fresh spinach or sautéed mushrooms with the sausage for extra nutrition. The base recipe is endlessly forgiving—it rewards experimentation rather than punishing it.

Serving Suggestions

A simple green salad with vinaigrette cuts through the richness beautifully. Fresh fruit on the side adds brightness and color. Keep hot sauce on the table—some guests always want that extra kick.

• Warm plates make a surprising difference in serving temperature
• Serve with good coffee and mimosas for the full brunch experience
• This casserole pairs perfectly with roasted potatoes on the side

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Theres nothing quite like the sound of forks scraping against plates, everyone going back for seconds. This is the dish that turns strangers into friends and makes family feel like home.

Recipe Questions & Answers

→ Can I prepare this breakfast casserole the night before?

Absolutely. Assemble the entire dish, cover tightly, and refrigerate overnight. When ready to bake, add about 10 extra minutes to the covered baking time since it will be starting from a cold temperature.

→ What type of bread works best for this casserole?

Day-old French bread or sourdough works exceptionally well because the slightly stale cubes absorb the egg mixture without becoming too mushy. You can also use country bread, Italian bread, or even hearty sandwich bread cut into cubes.

→ Can I make this breakfast casserole vegetarian?

Yes. Substitute the breakfast sausage with plant-based sausage crumbles, or use sautéed vegetables like mushrooms, spinach, bell peppers, and diced potatoes instead. You may want to increase the salt and spices slightly since sausage adds significant seasoning.

→ How do I know when the casserole is fully cooked?

The casserole is done when the center is set and no longer jiggles when you gently shake the pan, the top is golden brown, and a knife inserted into the center comes out clean. The internal temperature should reach 160°F (71°C) for food safety.

→ Can I freeze this breakfast casserole?

Yes, you can freeze it either before or after baking. For unbaked casseroles, wrap tightly and freeze for up to 3 months. Thaw overnight in the refrigerator before baking. For already-baked leftovers, cut into portions, wrap individually, and freeze for 2-3 months. Reheat in the microwave or oven.

→ What can I serve with this breakfast casserole?

Fresh fruit, a simple green salad, or roasted vegetables balance the richness. For brunch, consider serving alongside hash browns, breakfast potatoes, or fresh baked goods. Hot sauce, salsa, or sliced avocado make excellent toppings for extra flavor and freshness.