Looking for an easy and delicious breakfast that’s perfect for holidays, brunch, or just a cozy morning at home? This Croissant Breakfast Casserole with Sausage is exactly what you need! It’s loaded with everything you love—buttery croissants, savory sausage, cheese, eggs, and veggies—all baked together into one delicious casserole.
This overnight Croissant Breakfast Casserole with Sausage casserole is perfect for making ahead and cooking later, so you can enjoy a stress-free morning. Packed with carbs, protein, and veggies, it’s the perfect way to start the day and fuel up for anything ahead!
For more breakfast recipe ideas, check out these: Tater Tot Breakfast Casserole, Hamburger Hashbrown Casserole, and Cheesy Hashbrown Casserole.
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Ingredients for Croissant Breakfast Casserole with Sausage:
Here are the simple ingredients you'll need to make this flavorful casserole:
- Plain Croissants – Flaky and buttery, they form the perfect base for this dish.
- Sweet Italian Sausage – I used Trader Joe's sweet Italian chicken sausage for a lighter option, but pork sausage will also work wonderfully.
- Mushrooms – Fresh white mushrooms (or brown mushrooms) add earthy flavor and texture.
- Green Onion – Adds a mild onion flavor and a pop of color.
- Fresh Spinach & Red Bell Pepper – Packed with veggies, these ingredients bring color, freshness, and nutrition.
- Eggs – The key binder for the casserole, helping everything stick together.
- Whole Milk & Heavy Cream – These give the casserole a rich, creamy texture.
- Italian Seasoning, Salt & Black Pepper – For seasoning to taste.
- Cheese – A blend of Gruyère and mild Cheddar cheese makes the casserole extra cheesy and delicious.
- Olive oil. To sauté the ingredients.
These ingredients come together to create a balanced breakfast casserole that’s both hearty and full of flavor, perfect for any holiday or special occasion!
How to Make Croissant Breakfast Casserole with Sausage:
Making this Croissant Breakfast Casserole with Sausage is simple and quick! Here’s how to put it all together:
- Prepare the Croissants: Preheat your oven to 350°F (175°C). Slice a croissant in half lengthwise then bake them for 12-15 minutes, until they’re golden and slightly crispy. Once baked, break them into small chunks and set aside.
- Cook the Sausage and Veggies: Heat a bit of oil in a large skillet over medium-high heat. Add the sausage and cook for 3-5 minutes until browned and cooked through. Next, add the mushrooms, red bell pepper, green onion, and Italian seasoning. Cook for another 3-4 minutes, stirring occasionally, until the veggies soften. Add spinach and cook until wilted. Remove from heat, drain excess liquid then set aside.
- Assemble the Casserole: Transfer the croissant chunks to a baking dish.
- Add Veggies and Sausage: Spoon the sausage and veggie mixture over the croissants.
- Add Cheese: Sprinkle the shredded Gruyère and Cheddar cheese evenly on top.
- Make the Egg Mixture: In a separate bowl, whisk together the eggs, whole milk, heavy cream, salt, and black pepper. Pour this mixture evenly over the croissant and sausage layers in the baking dish.
- Let it Set: Cover the baking dish with foil or plastic wrap. Let the casserole sit in the fridge for at least 4 hours or overnight. This allows the bread to soak up the egg mixture, making it rich and flavorful.
- Bake: Preheat your oven again to 350°F (175°C). Bake the casserole, uncovered, for 45 minutes, or until the top is golden and the casserole is cooked through.
This method ensures a perfect blend of texture and flavor, making it the perfect dish to enjoy without any morning stress!
Tips for Making the Perfect Croissant Breakfast Casserole with Sausage:
- Use Day-Old Croissants: If possible, use croissants that are a day or two old. Stale croissants absorb the egg mixture better and will give the casserole a fluffier texture.
- Customize Your Sausage: While I used chicken sausage for a lighter option, you can switch it up with pork sausage, turkey sausage, or even a vegetarian sausage if you prefer. Just make sure to cook it thoroughly before adding to the casserole.
- Add Extra Veggies: If you’re looking to pack in even more nutrition, feel free to add other veggies like zucchini, broccoli, or tomatoes. These will add great flavor and color to your dish!
- Cheese Variations: While I recommend using a blend of Gruyère and Cheddar for a balance of flavor and melt, you can experiment with other cheeses like Monterey Jack, Swiss, or even feta for a different twist.
- Bacon Option: You can even add bacon to this casserole if you like! Crisp up some bacon and crumble it on top of the sausage mixture for an extra savory kick.
- Don’t Skip the Overnight Step: Allowing the casserole to sit in the fridge for several hours (or overnight) helps the bread soak up the egg mixture, giving the casserole a rich, creamy texture. If you’re short on time, aim for at least 4 hours of resting time.
- Make Ahead for Busy Mornings: This casserole is a perfect make-ahead breakfast. You can prepare it the night before and bake it the next morning for a hassle-free, delicious breakfast.
- Check for Doneness: When baking, make sure the casserole is fully set. You can test it by inserting a knife into the center—if it comes out clean, it’s done!
- Add Fresh Herbs: Top the casserole with fresh herbs like parsley, chives, or basil right before serving to add a burst of fresh flavor and color.
- Serving Suggestions: Pair your casserole with a side of fruit, a simple green salad, or even a dollop of sour cream or salsa for a complete breakfast or brunch spread.
With these tips, you’ll be sure to make a flavorful, perfectly baked croissant breakfast casserole that everyone will love!
Storage:
To store leftover croissant breakfast casserole, let it cool completely before covering it tightly with plastic wrap or aluminum foil. Refrigerate it for up to 3-4 days, or freeze individual portions for up to 2-3 months. Reheat thoroughly before serving.
Reheating:
To reheat leftover croissant breakfast casserole, preheat your oven to 350°F (175°C). Cover the casserole with foil and bake for 15-20 minutes, or until heated through. For individual portions, microwave on a microwave-safe plate for 1-2 minutes, or until hot, depending on the size.
📖 Recipe
Croissant Breakfast Casserole with Sausage
Equipment
- a large baking dish (9x13 inch)
- a spatula
Ingredients
- 1 pound plain butter croissant
- 1 pound sweet Italian sausage
- 1½ tablespoons olive oil
- 6 green onions , (chopped)
- 1 teaspoon Italian seasoning
- 8 oz sliced white or brown mushrooms
- 1 red bell pepper, (diced)
- 1 cup freshly chopped spinach leaves
- 10 large eggs, (or about 8 jumbos)
- 2 cups whole milk
- 1 cup heavy cream
- 4 oz freshly shredded gruyere cheese
- 4 oz freshly shredded mild cheddar cheese
- 1½ teaspoons kosher salt
- ¼ teaspoon ground black pepper
Instructions
- Preheat oven to 350°F (175°C). Slice croissants in half, bake for 12 minutes or longer until golden and crispy, then break into small chunks and set aside.
- Heat oil in a skillet over medium-high heat. Cook sausage for 3-5 minutes until browned, then add mushrooms, bell pepper, green onion, and Italian seasoning. Cook for another 3-4 minutes until veggies soften. Add spinach and cook until wilted. Remove from the heat then drain excess liquid in a strainer. Set aside.
- Transfer croissant chunks to a 9x13 inch baking dish, top with sausage and veggies, then sprinkle with Gruyère and Cheddar cheese.
- In a bowl, whisk eggs, milk, cream, salt, and pepper, then pour evenly over the croissant and sausage layers.
- Cover the dish and refrigerate for at least 4 hours or overnight to let the bread soak up the egg mixture.
- Preheat oven to 350°F (175°C) and bake uncovered for 45 minutes, until golden and cooked through. Let rest for 10 minutes, then garnish with chopped scallions before serving.
Rika says
My family loved this loaded croissant breakfast casserole! It’s so filling and delicious.