This Croissant Breakfast Casserole features flaky croissants filled with sausage, onion, peppers, and cheese and baked with custardy eggs. I love making this for holiday breakfasts and brunches because it can all be prepped the night before so all you have to do is pop it in the oven in the morning and relax!

“This recipe is SO good and such a crowd pleaser. Even my husband, who’s not a “casserole” type person, went back for seconds and said he can’t wait to have it again. Did I mention I’m making this for a second time in the past two weeks, so I can share it with everyone else?” -Kathleen, So Much Food reader

The Croissant Casserole I Always Make for Holiday Breakfasts

We love make-ahead breakfast casseroles at our house, and this sausage and croissant version is no exception! They’re perfect for stress-free mornings whether for birthdays, holidays, or just a special Sunday breakfast.

This croissant breakfast casserole is loaded with buttery croissants, sausage, onions, peppers, and cheese baked with custardy eggs. It’s a hearty and delicious breakfast that feeds a crowd. Imagine a hearty sausage scramble, but with toasty bits of croissant and that’s what you’ve got here.

This recipe is easy to customize for your guests and is such a crowd pleaser.

Tools You’ll Need

• 9×13 Baking Dish
• Baking Sheet
• Skillet
• Sharp Knife
• Mixing Bowl
• Whisk

The Main Ingredients

• Croissants. Buy pre-baked small croissants from the bakery section of your grocery store, not croissant dough in a tube.
• Ground breakfast sausage. Use your favorite breakfast sausage here! Buy the ground sausage, not the cased sausage. If it’s in casings, you’ll have to remove the meat from the casings.
• Peppers and onions. A classic combo! Use whatever colors you like.
• Eggs. Use large eggs at room temperature.
• Half and half. Don’t downgrade to milk; the fat in the half and half makes the eggs custardy and delicious without being spongy.
• Cheese. I used white cheddar, but you can use anything you like!
• Cream cheese. Cream cheese helps bind the filling. Make sure to bring your cream cheese to room temperature.
• Spices and seasonings. Paprika, hot sauce, dijon mustard, and everything bagel seasoning make this breakfast casserole extra savory.
• Green onions. Top with some sliced green onions before serving.

How to Make Croissant Breakfast Casserole

Jenny’s Tip: I always use a ceramic or glass 9×13 baking dish for this recipe. I don’t recommend baking the casserole in aluminum.

1. Make the sausage filling. The ground sausage, bell peppers, and onion are cooked in a skillet until the meat is browned and the veggies are soft. Add the sausage mixture to a mixing bowl and combine with the softened cream cheese, paprika, cream cheese, and green onions.
2. Fill the croissants. Cut the croissants in half length-wise and arrange the bottom halves in a 9×13-inch baking dish. Spoon the sausage filling over the croissants and then pop on the top halves.
3. Pour over the eggs. I like to blitz the eggs, half and half, Dijon, hot sauce, and seasonings in a blender for ease, but you can do this in a mixing bowl too. Pour the smooth egg mixture over the croissants.
4. Let chill in the fridge for at least 1 hour, then bake. I like to top the croissants with everything bagel seasoning and shredded cheese before baking for a pretty presentation.

Make-Ahead Option

You can make this as an overnight breakfast casserole with croissants. Simply prepare the recipe through step #5 in the recipe card below, which has you pour the egg mixture over the croissants and let them soak in the fridge.

Instead of soaking the croissants for 1 hour, cover the pan tightly and leave them to soak overnight.

Don’t prep this too far in advance! The earliest I would prep this casserole is the night before you plan to serve it (10-12 hours in advance).

Ways to Customize Your Casserole

There are so many ways to adjust this recipe! Think of this sausage croissant breakfast casserole as a blueprint that you can adjust to your tastes and what you have on hand. Here are my favorite ways to mix things up:

• Try a different meat. Any ground meat here would work! I love breakfast sausage, but you can swap anything in. You could also use finely diced ham and bacon mixed together for almost a Denver scramble kind of casserole.
• Swap a different cheese. White cheddar is classic, but there are so many options! Gruyere, sharp cheddar, Swiss, and even crumbled goat cheese or feta would be incredible here.
• Add some veggies. If you want to add a bit more texture and sneak in some veggies, this is the chance to do so! You could add some sautéed spinach or kale, mushrooms, diced tomatoes, jalapeño, zucchini, etc. The sky is the limit here!

What to Serve with This Casserole

We always have a Christmas brunch gathering and we make a whole spread. This Croissant Breakfast Casserole is definitely on the list this year along with Homemade NY Style Bagels, Salmon Gravlax, Smoked Salmon Spread, and Cranberry-Almond Danishes.

Other drinks and sides to serve with this croissant casserole include:

• Irish Coffee or Boozy Eggnog (c’mon, it’s the holidays!)
• Homemade Hot Chocolate
• Fruit Salad
• Breakfast Potatoes
• Puff Pastry Apple Strudel

More Make-Ahead Holiday Breakfast Recipes

• Bacon-Leek Frittata
• Quiche Lorraine
• Apple Pie French Toast Bake
• Ham and Cheese Croissant Bake
• Pumpkin Cinnamon Rolls
• Bananas Foster French Toast Casserole