Overnight Sausage and Cheese Breakfast Casserole

By AislePrompt Editorial · Published 2026-04-26 · Updated 2026-04-26

A savory overnight breakfast casserole layered with browned sausage, sharp cheddar cheese, and a custardy egg mixture, perfect for a festive Christmas morning. This American-inspired Christmas recipe, ready in about 65 minutes, combines ground breakfast sausage, large eggs, whole milk into a breakfast that fuels the morning without the midday crash — make-ahead-friendly and balanced enough to anchor the first meal of the day. Each serving lands at about 390 calories and feeds 8, so it sits comfortably in a weekly breakfast rotation alongside fruit, yogurt, or coffee. Tap "Plan a meal with the AI" below to drop this recipe into your week and send the ingredients straight to Instacart. Nutrition values are approximate, calculated from USDA FoodData Central (fdc.nal.usda.gov) — verify against ingredient labels for any health-driven dietary plan.

Ingredients

• 1 pound ground breakfast sausage
• 8 large eggs
• 2 cups whole milk
• 6 cups sourdough bread cubes
• 2 cups sharp cheddar cheese shredded
• 1 tsp salt
• 1/2 tsp black pepper
• 1 tbsp yellow mustard
• 1 tbsp butter for greasing

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Instructions

1. Step 1: Preheat oven to 350°F and butter a 9x13-inch baking dish with 1 tbsp butter to prevent sticking.
2. Step 2: In a skillet over medium heat, cook 1 pound ground breakfast sausage, breaking it apart with a spoon, until browned and no longer pink, about 7 minutes; drain excess fat.
3. Step 3: In a large bowl, whisk together 8 large eggs, 2 cups whole milk, 1 tsp salt, 1/2 tsp black pepper, and 1 tbsp yellow mustard until smooth and combined.
4. Step 4: Layer 6 cups sourdough bread cubes evenly in the prepared dish, then sprinkle the cooked sausage evenly over the bread.
5. Step 5: Sprinkle 2 cups shredded sharp cheddar cheese evenly on top of the sausage layer.
6. Step 6: Pour the egg mixture evenly over the entire casserole, pressing down gently with a spatula to soak the bread.
7. Step 7: Cover the dish tightly with foil and refrigerate overnight.
8. Step 8: The next morning, remove foil and bake uncovered at 350°F for 45-50 minutes until the top is golden and the casserole is set in the center.
9. Step 9: Let cool for 5 minutes before slicing and serving warm.