Description

A rich, savory breakfast casserole featuring buttery croissants, sausage, and sharp cheddar cheese in a creamy egg custard. This make-ahead meal is perfect for weekend brunches and requires minimal prep time.

Ingredients

Scale

8 to 10 large butter croissants (about 600g), day-old
2 tablespoons butter (optional, for brushing)
1 pound breakfast sausage (mild Italian or pork)
2 cups sharp cheddar cheese, shredded (from a block)
1 small red onion, finely diced
8 large eggs
1 cup heavy cream
1 cup whole milk
1 tablespoon Dijon mustard
1 teaspoon dried thyme
Salt and black pepper to taste
2 cups fresh spinach (optional)

Instructions

Preheat oven to 350°F (175°C) and grease a 9×13 inch baking dish.
Heat a large skillet over medium-high heat and cook the sausage, crumbling it into small pieces until browned and crispy. Drain excess grease and set aside.
Tear the croissants into bite-sized pieces and spread them evenly in the prepared baking dish.
Scatter the cooked sausage, diced onion, and optional spinach over the croissants. Sprinkle the shredded cheddar cheese evenly on top.
In a large bowl, vigorously whisk together the eggs, heavy cream, milk, Dijon mustard, thyme, salt, and pepper until uniform and slightly frothy.
Pour the egg mixture evenly over the bread. Use a spatula to gently press down on the bread to ensure every piece is submerged.
Let the casserole sit for 10-15 minutes to allow the bread to absorb the liquid (or cover and refrigerate overnight if making ahead).
Bake for 45-50 minutes until the top is golden brown, puffy, and set. If browning too fast, tent with foil for the last 10 minutes.
Remove from oven and let rest for 10 minutes before cutting and serving to allow the custard to set.

Notes

Use day-old or stale croissants to prevent a soggy texture. If using fresh croissants, let them sit open-faced for an hour or bake at 300°F for 5 minutes to dry them out. Always grate your own cheese to ensure smooth melting. Let the casserole rest for 10 minutes after baking to allow the custard to set properly. Drain sausage grease thoroughly to avoid an oily casserole.

Prep Time: 15 minutes
Cook Time: 45-50 minutes
Category: Breakfast
Cuisine: American

Nutrition

Serving Size: 1 square
Calories: 480
Fat: 28
Saturated Fat: 12
Carbohydrates: 35
Fiber: 1
Protein: 22

Keywords: breakfast casserole, croissant casserole, make-ahead breakfast, sausage breakfast, brunch recipe, easy breakfast, cheesy breakfast