Description
This delicious Overnight Croissant Breakfast Bake combines buttery toasted croissants with sautéed spinach, mushrooms, and sweet onions, all soaked in a rich custard of eggs, milk, and cream. Topped with melted Gruyere and Parmesan cheese, it’s an easy make-ahead dish perfect for a hearty breakfast or brunch.
Ingredients
Scale
- 5 to 7 large croissants, sliced in half lengthwise
- 2 tablespoons unsalted butter
- 1 sweet onion, diced
- 2 garlic cloves, minced
- 10 ounces cremini mushrooms, chopped
- 8 ounces fresh baby spinach
- Kosher salt and pepper, to taste
- 8 large eggs
- 2 ½ cups milk
- 1 cup heavy cream
- 8 ounces Gruyere cheese, freshly grated
- Fresh chopped parsley, for topping
- Parmesan cheese, for topping
Instructions
- Preheat the oven to 450 degrees F. Place the croissants cut-side up on a baking sheet and bake for 5 to 8 minutes until toasty. Remove and let cool slightly, then chop or tear into pieces.
- Heat butter in a large skillet over medium-low heat. Add diced onions and minced garlic; cook for 5 minutes until softened. Add chopped mushrooms and cook for another 5 minutes until plump and juicy. Stir in the baby spinach and cook until wilted. Season with kosher salt and pepper.
- Brush a 9×13 inch baking dish with melted butter. Combine croissant pieces and sautéed vegetable mixture in the dish, tossing well to combine.
- In a large bowl, whisk together eggs, milk, heavy cream, and a large pinch of salt and pepper. Stir in 1 cup of grated Gruyere cheese and optionally some fresh chopped herbs like parsley or chives.
- Pour the egg mixture over the croissant and vegetable mixture in the baking dish. Press the croissants gently into the egg liquid to ensure they absorb it. Cover the dish with plastic wrap and refrigerate for 8 hours or overnight.
- Preheat the oven to 350 degrees F. Remove the dish from the fridge 30 minutes before baking to take off the chill. Remove plastic wrap, top the casserole with the remaining grated Gruyere cheese, and bake uncovered for 45 minutes until set and golden.
- Sprinkle extra Parmesan cheese and fresh chopped parsley on top before serving. Enjoy warm for breakfast or brunch!
Notes
- Prep Time: 30 minutes
- Cook Time: 1 hour
- Category: Breakfast
- Method: Baking
- Cuisine: French
Nutrition
- Serving Size: 1 serving
- Calories: 380
- Sugar: 3 g
- Sodium: 600 mg
- Fat: 24 g
- Saturated Fat: 12 g
- Unsaturated Fat: 8 g
- Trans Fat: 0 g
- Carbohydrates: 27 g
- Fiber: 1 g
- Protein: 15 g
- Cholesterol: 200 mg