Description
Flaky, buttery croissants baked in a rich egg custard with cheese, ham, and herbs this Overnight Croissant Breakfast Casserole is the ultimate make-ahead brunch dish for holidays or lazy weekends.
Ingredients
6 large croissants, torn into large pieces
1 1/2 cups diced ham (or cooked bacon/sausage)
1 1/2 cups shredded cheddar cheese
1/2 cup shredded mozzarella or Swiss cheese
6 large eggs
2 cups milk
1/2 cup heavy cream
1 tsp Dijon mustard
1/2 tsp garlic powder
1/2 tsp salt
1/4 tsp black pepper
2 tbsp chopped green onions or chives
Butter or cooking spray for greasing
Instructions
1. Grease a 9×13-inch baking dish with butter or cooking spray.
2. Arrange torn croissant pieces evenly in the dish.
3. Sprinkle diced ham and cheeses evenly over the croissants.
4. In a large bowl, whisk together eggs, milk, cream, Dijon mustard, garlic powder, salt, and pepper until well combined.
5. Pour the egg mixture evenly over the croissant and ham mixture, pressing gently to ensure the croissants soak up the liquid.
6. Cover tightly with foil or plastic wrap and refrigerate overnight (at least 6 hours).
7. When ready to bake, preheat oven to 350°F (175°C).
8. Remove the casserole from the fridge and let sit at room temperature for 20 minutes.
9. Bake uncovered for 40–45 minutes, or until golden and puffed, and the center is set.
10. Sprinkle with green onions or chives before serving warm.
Notes
You can customize this casserole with vegetables like spinach, bell peppers, or mushrooms.
Use leftover croissants that are slightly stale — they absorb the custard best.
For a sweet version, skip the ham and cheese and use cream cheese, berries, and a cinnamon-vanilla custard instead.
- Prep Time: 15 mins
- Cook Time: 45 mins
- Category: Breakfast
- Method: Baked
- Cuisine: American
Nutrition
- Serving Size: 1 slice
- Calories: 420
- Sugar: 4g
- Sodium: 890mg
- Fat: 30g
- Saturated Fat: 15g
- Unsaturated Fat: 13g
- Trans Fat: 0g
- Carbohydrates: 22g
- Fiber: 1g
- Protein: 20g
- Cholesterol: 215mg
Keywords: Overnight croissant breakfast casserole, make ahead brunch, ham and cheese bake, savory breakfast, holiday casserole