Easy Overnight Christmas Breakfast Casserole
Christmas morning in my house used to be chaos. Everyone was up early, the kids wanted to open presents, and I was standing in the kitchen trying to cook eggs for a crowd. Then I started making this overnight Christmas breakfast casserole, and honestly, it changed the whole morning.
You put it together the night before, pop it in the fridge, and bake it in the morning. That’s it. While it bakes, the house smells amazing and you actually get to sit with your family and drink your coffee.
It has soft bread, savory sausage, eggs, a little bell pepper and a lot of melty cheddar. The bread soaks up the egg mixture overnight, so it bakes into something between a strata and a savory bread pudding. Crispy cheesy top, soft custardy middle.
Why You’ll Love This Christmas Breakfast Casserole
- Made the night before. All the work is done on Christmas Eve, so your morning stays calm.
- Feeds a crowd. One 9×13 pan gives you about 12 servings.
- Simple ingredients. Bread, eggs, milk, sausage and cheese. Nothing fancy.
- Easy to change. Swap the meat, add veggies or use a different cheese.
- Kid-approved. In my experience, even picky eaters go back for seconds.
Ingredients You’ll Need
The full amounts are in the recipe card below, but here are a few notes on the main ingredients.
- Bread: Day-old French bread or a sturdy white loaf works best. Fresh, soft bread turns mushy. If your bread is fresh, cube it and leave it out for a few hours, or toast the cubes in the oven for 10 minutes.
- Breakfast sausage: Pork, turkey or chicken sausage all work. Just brown it well and drain the extra grease.
- Eggs and milk: This is the custard that holds everything together. Whole milk gives the creamiest result.
- Sharp cheddar: Sharp cheddar has more flavor than mild. Shredding your own block melts better than pre-shredded.
- Bell pepper and green onion: They add color, which makes it look festive on the table. Red and green peppers are perfect for Christmas.
- Dry mustard: You won’t taste mustard, but it makes the cheese and eggs taste richer. Dijon works too.
How to Make Overnight Christmas Breakfast Casserole
- Brown the sausage. Cook it in a skillet, break it into small pieces, and drain the grease.
- Layer the casserole. Spread the bread cubes in a greased 9×13 dish. Add the sausage, peppers, green onion and most of the cheese.
- Whisk the egg mixture. Whisk the eggs, milk and seasonings, then pour it evenly over the bread.
- Press and chill. Gently press the bread down so every piece gets wet. Cover and refrigerate overnight.
- Bake in the morning. Let it sit out for 30 minutes, add the rest of the cheese, and bake until the center is set.
My Tips for the Best Breakfast Casserole
- Don’t skip the overnight rest. The first time I rushed it and baked it after an hour, the middle was soggy. At least 8 hours gives the bread time to soak up the custard.
- Take it out of the fridge first. A cold glass dish going straight into a hot oven can crack, and the middle cooks unevenly. 30 minutes on the counter fixes both.
- Bake covered, then uncovered. Foil for the first 30 minutes keeps the top from burning. Removing it at the end gives you that golden, bubbly cheese.
- Check the center. Insert a knife in the middle. If it comes out clean with no runny egg, it’s done. A thermometer should read 160°F (71°C).
- Let it rest 10 minutes. It slices much cleaner once it sets.
Variations to Try
- Ham and Swiss: Use diced ham instead of sausage and Swiss instead of cheddar. Great for leftover Christmas ham.
- Bacon and cheddar: Use 10 to 12 slices of cooked, crumbled bacon.
- Vegetarian: Skip the meat and add sautéed mushrooms, spinach and onions.
- Southwest style: Add green chiles, use pepper jack, and serve with salsa.
- Hash brown version: Replace the bread with a 30 oz bag of thawed shredded hash browns.
Make-Ahead, Storage and Reheating
- Make ahead: Assemble up to 24 hours before baking.
- Fridge: Store leftovers covered for up to 4 days.
- Freeze: Freeze baked slices wrapped tightly for up to 3 months. Thaw overnight in the fridge.
- Reheat: Microwave a slice for 60 to 90 seconds, or warm the whole dish at 350°F (175°C) for 15 to 20 minutes, covered.
What to Serve With It
I like to keep the rest of the table simple: a big bowl of fresh fruit, cinnamon rolls or muffins, and plenty of coffee or hot chocolate. It also pairs really well with a fruit salad with pomegranate seeds for extra Christmas color.
Frequently Asked Questions
Can I bake it the same day? Yes, but let it soak for at least 1 to 2 hours. Overnight gives the best texture.
Why is my breakfast casserole soggy in the middle? Usually it’s underbaked, or the bread was too fresh. Use day-old bread and bake until a knife in the center comes out clean.
Can I use a smaller pan? Yes. Halve the recipe and use an 8×8 dish. Start checking it about 10 minutes earlier.
Can I make it without sausage? Absolutely. Use ham, bacon, or keep it vegetarian with mushrooms and spinach.
Can I freeze it before baking? I prefer freezing it after baking. Unbaked, the bread can get watery once thawed.
One Last Thing
This casserole has become a Christmas morning tradition for us, and I hope it becomes one in your house too. If you make it, leave a comment and a star rating below. I love hearing how it turned out. And don’t forget to save it to your Christmas board on Pinterest so you can find it again next year!
Overnight Christmas Breakfast Casserole
Ingredients
Casserole:
- 1 lb breakfast sausage pork, turkey or chicken
- 8 cups day-old French bread cut into 1-inch cubes (about one 1 lb loaf)
- 1/2 cup red bell pepper diced
- 1/2 cup green bell pepper diced
- 1/3 cup green onions sliced
- 2 cups sharp cheddar cheese shredded (divided)
- 1 tablespoon butter for greasing the dish
Egg Mixture:
- 10 large eggs
- 2 1/2 cups whole milk
- 1 teaspoon dry mustard or 1 teaspoon Dijon mustard
- 1 teaspoon salt
- 1/2 teaspoon black pepper
- 1/2 teaspoon garlic powder
Instructions
- Cook the sausage in a large skillet over medium-high heat, breaking it into small crumbles, until browned and cooked through, about 8 to 10 minutes. Drain the grease and let it cool slightly.
- Grease a 9×13 baking dish with butter. Spread half of the bread cubes in the dish.
- Sprinkle half of the sausage, half of the bell peppers, half of the green onions and 3/4 cup of cheddar over the bread. Repeat with the remaining bread, sausage, peppers, onions and another 3/4 cup of cheese. Save the last 1/2 cup of cheese for the morning.
- In a large bowl, whisk the eggs, milk, dry mustard, salt, pepper and garlic powder until smooth.
- Pour the egg mixture evenly over the casserole. Gently press the bread down with a spatula so every piece is soaked.
- Cover tightly with foil or plastic wrap and refrigerate for at least 8 hours or overnight.
- In the morning, take the casserole out of the fridge and let it sit on the counter for 30 minutes. Preheat the oven to 350°F (175°C).
- Remove any plastic wrap, cover the dish with foil and bake for 30 minutes.
- Uncover, sprinkle the remaining 1/2 cup of cheese on top and bake for another 20 to 25 minutes, until the top is golden and a knife inserted in the center comes out clean (160°F / 71°C).
- Let the casserole rest for 10 minutes before slicing and serving.
Notes
Make ahead: Assemble up to 24 hours before baking.
Storage: Keep leftovers covered in the fridge for up to 4 days, or freeze baked slices for up to 3 months.
Reheat: Microwave single slices for 60 to 90 seconds, or reheat the whole dish covered at 350°F (175°C) for 15 to 20 minutes.
Variations: Swap the sausage for diced ham or crumbled bacon, use Swiss or pepper jack instead of cheddar, or make it vegetarian with mushrooms and spinach.
