For over 40 years, this casserole has been my family’s Christmas morning tradition. My mom made it every holiday, and now I do the same for my own family. There’s something magical about waking up on a special morning with your kitchen already clean, your dishes already done, and knowing that all you have to do is slide a pan into the oven. This easy overnight casserole layers buttered bread, melty cheese, savory sausage, and green chiles, all soaked in a seasoned egg custard that sits overnight to develop incredible flavor.
Why you’ll love this dish
This make-ahead breakfast casserole is the ultimate stress-free holiday morning solution. You do all the work the night before, which means you can actually enjoy your special morning instead of being stuck in the kitchen. It feeds a crowd (12 servings), uses simple everyday ingredients, and tastes absolutely delicious—rich, cheesy, and satisfying.
The overnight soak is what makes this casserole special. The bread absorbs all that seasoned egg mixture, the flavors meld together beautifully, and you end up with a dish that’s custardy in the center with golden, crispy edges. It’s perfect for Christmas morning, Easter brunch, Mother’s Day, or any time you’re hosting overnight guests and want to serve something impressive without morning chaos.
“My mom just made this for a Christmas brunch the women in our family had together. It was so good we stuffed ourselves and didn’t save room for the cheesecake dessert!” — crownofflora79
How this recipe comes together
The assembly process is straightforward and takes about 15 minutes. You’ll start by trimming the crusts off white sandwich bread, buttering one side, and arranging the slices butter-side-down in your baking dish like a puzzle to cover the bottom completely. Then you’ll layer on freshly shredded cheese (a mix of Jack and cheddar), followed by your pre-cooked crumbled sausage and green chiles straight from the can.
The magic happens when you whisk together eggs, milk, and a blend of seasonings—salt, pepper, oregano, paprika, garlic powder, and dry mustard. You’ll give this mixture one final whisk right before pouring it evenly over your assembled layers. This is important because it ensures the spices are evenly distributed rather than settling in one spot. The whole dish then goes into the refrigerator overnight, allowing the bread to soak up all that flavorful custard. In the morning, you simply pop it in a preheated oven for about an hour.
What you’ll need
Base layers:
- 6-8 slices plain white sandwich bread — Fresh, soft white bread works best here; avoid dried-out French bread
- Butter, very soft — Real butter for spreading; you’ll butter one side of each slice
- 2 cups Jack cheese, shredded — Freshly shredded from a block for better melting
- 2 cups cheddar cheese, shredded — Also freshly shredded; avoid pre-shredded bags
Protein and flavor:
- 12 ounces pork sausage — Crumbled and browned before assembly; Jimmy Dean is recommended
- 1 (4-ounce) can green chiles — No need to drain; the juice adds flavor
Egg custard:
- 6 large eggs
- 2 cups milk
Seasonings:
- 1 teaspoon kosher salt
- ½ teaspoon paprika
- 1 teaspoon oregano
- ½ teaspoon black pepper
- ¼ teaspoon garlic powder
- ¼ teaspoon dry mustard
Step-by-step instructions
- Prepare the bread: Remove the crusts from your bread slices and lightly butter one side of each piece. Arrange the bread butter-side-down in a 9×13-inch baking dish, cutting pieces as needed to fit together like a puzzle and cover the bottom with no large gaps.
- Add the cheese layer: Grate your Jack and cheddar cheeses fresh from the block. Sprinkle both cheeses evenly over the bread layer, making sure to reach the corners.
- Layer the sausage and chiles: Make sure your sausage is already cooked and crumbled before you begin. Scatter the browned sausage evenly over the cheese. Use your hands to grab the green chiles from the can and sprinkle them over the sausage—don’t worry about draining; the small amount of juice that comes along is fine.
- Make the egg mixture: In a medium mixing bowl, whisk the eggs until well combined. Add the milk and all your seasonings (salt, paprika, oregano, pepper, garlic powder, and dry mustard). Whisk everything together thoroughly.
- Pour and soak: Give your egg mixture one final good whisk immediately before pouring. This prevents the spices from settling at the bottom and ensures even distribution. Pour the mixture slowly and evenly over your assembled casserole, making sure it reaches all the edges.
- Refrigerate overnight: Cover the dish well with plastic wrap or aluminum foil. Place it in the refrigerator for at least 8 hours or overnight. This allows the bread to fully absorb the liquid and the flavors to develop.
- Bake in the morning: When you’re ready to cook, preheat your oven to 350°F. Remove the cover and bake uncovered for 50-60 minutes. The center should be puffed and set (no longer jiggly), and the edges should be golden brown. Let the casserole cool for about 10 minutes before cutting and serving.
Serving suggestions
Serve this hearty casserole with fresh fruit on the side—a colorful fruit salad with berries, melon, and grapes provides a refreshing contrast to the rich, savory flavors. Hash browns or breakfast potatoes make excellent companions if you want a more filling spread.
For a complete holiday brunch table, pair it with overnight yeasted waffles, fresh-squeezed orange juice, and cinnamon rolls. The casserole cuts beautifully into squares, making it easy to plate individual servings. Garnish each plate with a sprig of fresh parsley or a sprinkle of chopped green onions for a pop of color.
Coffee bar extras like flavored syrups and whipped cream turn your breakfast into a special occasion. Consider setting out hot sauce or salsa for guests who like extra heat.
Keeping leftovers fresh
Store leftover casserole in an airtight container in the refrigerator for 3-4 days. The casserole reheats well, though the texture will be slightly less fluffy than when freshly baked.
For best reheating results, cut your piece of casserole into smaller portions before microwaving. This helps it heat more evenly throughout. Microwave individual portions for 1-2 minutes, checking at 30-second intervals until heated through.
You can also reheat in a 300°F oven covered with foil for about 15-20 minutes if you’re warming several servings at once. This method helps maintain the texture better than the microwave.
While you can freeze this casserole after baking, the texture of the eggs may become slightly watery upon thawing. If you do freeze it, wrap portions tightly in plastic wrap and aluminum foil, and use within 2 months. Thaw overnight in the refrigerator before reheating.
Pro chef tips
Always use fresh-shredded cheese: Pre-shredded cheese contains anti-caking agents like cellulose and sometimes preservatives like natamycin. These additives prevent the cheese from melting smoothly and creating that creamy, cohesive texture you want. Take the extra few minutes to shred from a block—it makes a real difference.
Don’t skip the butter-side-down step: Placing the buttered side down creates a barrier that prevents the bottom from getting soggy. The butter also adds richness and helps the bottom layer crisp up slightly around the edges.
Cook your sausage thoroughly and drain well: Excess grease in the casserole can make it oily. After browning your sausage, drain it on paper towels to remove extra fat before adding it to the dish.
Whisk before you pour: The spices in the egg mixture settle quickly. That final whisk right before pouring ensures every bite has balanced seasoning instead of some pieces being bland and others overly spiced.
Check the center: The casserole is done when the center is set and no longer jiggly. If you insert a knife in the center, it should come out mostly clean. The edges will be golden and may pull away slightly from the sides of the pan.
Let it rest: Allowing the casserole to cool for 10 minutes after baking helps it set up and makes cutting and serving much easier. It will still be hot and delicious, just not so hot that it falls apart.
Recipe variations
Vegetarian version: Skip the sausage and add sautéed mushrooms, bell peppers, and onions instead. You can also add spinach or diced tomatoes for extra vegetables and color.
Southwest style: Use pepper Jack cheese instead of regular Jack, add black beans and corn with the sausage, and top with fresh cilantro, diced avocado, and salsa after baking.
Italian twist: Replace the pork sausage with Italian sausage, use mozzarella and Parmesan instead of Jack and cheddar, and add sun-dried tomatoes. Season with Italian herbs instead of oregano.
Potato base: Swap the bread for cubed or shredded frozen hash browns for a gluten-free option. Use frozen potatoes straight from the bag—no need to thaw. You may need to add 10-15 minutes to the baking time.
Ham and Swiss: Replace sausage with diced ham and use Swiss cheese for a classic quiche-inspired flavor. Add a tablespoon of Dijon mustard to the egg mixture.
Spicy kick: Add diced jalapeños along with the green chiles, use hot breakfast sausage, and sprinkle red pepper flakes in the egg mixture. Top with hot sauce when serving.
Croissant upgrade: Use torn croissants instead of white bread for an extra-rich, buttery casserole. This turns it into more of a special occasion dish.
Your questions answered
Can I make this casserole ahead and freeze it unbaked? Yes! Assemble the casserole completely, cover it tightly with plastic wrap and aluminum foil, and freeze for up to 2 months. Thaw overnight in the refrigerator before baking as directed. You may need to add 5-10 minutes to the baking time if it’s still slightly cold in the center.
What type of sausage should I use? Use regular ground pork breakfast sausage found in the refrigerated section near the bacon. Avoid maple-flavored or sweet sausages, and steer clear of Italian sausage unless you’re intentionally making an Italian variation. Jimmy Dean is a popular choice, but any plain breakfast sausage works well.
Can I use a different type of bread? While white sandwich bread is recommended for its ability to absorb the egg mixture without falling apart, you can experiment. Some people successfully use French bread cubes, croissants, or even English muffins. Avoid very dense or seedy bread as it won’t absorb the custard as well. If you use cubed bread instead of sliced, you’ll get more of a strata texture.
Why does the recipe specify not to use pre-shredded cheese? Pre-shredded cheese contains additives like cellulose (wood pulp) to prevent clumping and sometimes preservatives. These additives interfere with how the cheese melts, often resulting in a grainy texture rather than the smooth, creamy consistency you want in this casserole. Freshly shredded cheese melts beautifully and creates better texture.
How do I know when the casserole is fully cooked? The center should be puffed up and set—no longer jiggly when you gently shake the pan. A knife inserted in the center should come out mostly clean with perhaps a bit of melted cheese. The edges should be golden brown and may pull away slightly from the sides. Internal temperature should reach 160°F.
Can I use milk alternatives? Yes, you can use unsweetened almond milk, oat milk, or soy milk if you need a dairy-free option. However, you’ll also need to replace the butter and cheese with dairy-free alternatives. The texture and flavor will be different from the original, but it can still work.
What if I don’t have a 9×13 pan? You can use two 8×8 or 9×9 pans and make smaller casseroles. You can also use an oven-safe 3-quart casserole dish. Just adjust your bread arrangement to fit the shape of your pan. Baking time may vary slightly with different pan sizes—check for doneness at 45 minutes if using shallower pans.
Print
Overnight Breakfast Casserole
- Total Time: 75 minutes
- Yield: 12 servings
- Diet: Gluten-Free
Description
A make-ahead breakfast casserole layered with buttered bread, cheese, sausage, and green chiles, soaked in a seasoned egg custard for a rich and comforting dish.
Ingredients
- 6-8 slices plain white sandwich bread
- Butter, very soft
- 2 cups Jack cheese, shredded
- 2 cups cheddar cheese, shredded
- 12 ounces pork sausage, crumbled and browned
- 1 (4-ounce) can green chiles
- 6 large eggs
- 2 cups milk
- 1 teaspoon kosher salt
- ½ teaspoon paprika
- 1 teaspoon oregano
- ½ teaspoon black pepper
- ¼ teaspoon garlic powder
- ¼ teaspoon dry mustard
Instructions
- Prepare the bread: Remove the crusts from your bread slices and lightly butter one side of each piece. Arrange the bread butter-side-down in a 9×13-inch baking dish.
- Add the cheese layer: Sprinkle the grated Jack and cheddar cheeses evenly over the bread layer.
- Layer the sausage and chiles: Scatter the browned sausage over the cheese and sprinkle the green chiles on top.
- Make the egg mixture: In a bowl, whisk together the eggs, milk, and seasonings.
- Pour and soak: Pour the egg mixture evenly over the casserole and cover it.
- Refrigerate overnight: Place in the refrigerator for at least 8 hours.
- Bake in the morning: Preheat the oven to 350°F, remove the cover, and bake for 50-60 minutes until golden brown.
Notes
Serve with fresh fruit, hash browns, or breakfast potatoes. Leftovers can be stored in an airtight container for 3-4 days.
- Prep Time: 15 minutes
- Cook Time: 60 minutes
- Category: Breakfast
- Method: Baking
- Cuisine: American