Overnight Breakfast Casserole
This overnight breakfast casserole combines layers of bread, browned sausage, and sharp cheddar cheese bound in a custard of eggs, half-and-half, and warm spices. Prepare it the night before and bake in the morning for a stress-free breakfast that feeds a crowd.
Total
1h 10mServings
8Ingredients
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13 Ingredients
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Instructions
- 1
In a skillet over medium-high heat, cook and crumble the breakfast sausage until browned. Drain any excess grease and set aside.
- 2
In a large bowl, crack the eggs and whisk them together.
- 3
Season the eggs with salt, black pepper, cayenne pepper, ground mustard, dried sage, and dried chives.
- 4
Pour in the half-and-half and whisk until the custard is smooth and well combined.
- 5
Grate the sharp yellow and extra-sharp white cheddar cheeses.
- 6
Cut the butter bread into 1-inch cubes.
- 7
Grease a 13x9 inch baking dish with butter. Layer the bread cubes, cooked sausage, and shredded cheeses in the dish.
- 8
Pour the egg custard mixture evenly over the layers in the baking dish.
- 9
Cover the dish and refrigerate overnight, or for at least 8 hours.
- 10
The next day, preheat your oven to 350°F. Remove the casserole from the refrigerator and let it sit at room temperature while the oven heats up.
- 11
Bake uncovered for 45 to 50 minutes, or until the center is set and the top is lightly golden brown.
- 12
Let the casserole rest for 5 minutes before cutting and serving.
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Tips & Notes
Pro tips
- Brown the sausage thoroughly before layering to render fat and develop flavor; break it into small crumbles for even distribution.
- Let the assembled casserole sit in the refrigerator for at least 8 hours so the bread fully absorbs the custard mixture.
- Cover with foil for the first 25–30 minutes of baking to prevent the top from browning too quickly, then uncover to finish cooking.
- Test doneness by inserting a knife near the center; it should come out clean or with moist crumbs, not wet custard.
Substitutions
- Breakfast sausage → Italian sausage or ground turkey (adjust seasoning, as Italian sausage is already herbed)
- Half-and-half → whole milk or light cream (result will be slightly less rich)
- Sharp yellow cheddar → white cheddar or aged Gruyère (maintain bold cheese flavor)
- Dried sage → fresh sage leaves, finely chopped (use half the amount, add just before baking)
Storage & make-ahead
Store covered in the fridge for up to 3 days. Reheat individual portions in the microwave (1–2 minutes) or cover and warm in a 325°F oven until heated through.
Common Questions
Can I assemble this casserole the night before?
Yes, that's the whole point. Assemble completely, cover with foil, refrigerate overnight, then bake in the morning. The bread absorbs the custard as it sits.
What type of bread works best?
Use a sturdy bread like sourdough, challah, or brioche. Avoid soft sandwich bread, which gets mushy. Slightly stale bread works even better.
Can I make this ahead and freeze it?
Yes, assemble and freeze unbaked for up to 3 months. Thaw overnight in the fridge, then bake as directed, adding 10–15 minutes to baking time.
How do I know when the casserole is done baking?
The custard should be set but slightly jiggly in the very center. A knife inserted near the center should come out clean or with moist crumbs, not wet custard.
Can I use a different cheese?
Yes. Gruyère, Swiss, or a mild cheddar blend work well. Sharp cheddar adds the most flavor; use less of a milder cheese or the dish may taste bland.
