A rich and comforting start to the day, this Overnight Croissant Breakfast Casserole combines buttery croissants with creamy eggs and melty cheese. I prep it the night before so that in the morning, I can simply bake and serve. It’s the kind of dish that turns simple ingredients into something special—perfect for holiday mornings, brunch with friends, or a relaxed weekend breakfast.
Ingredients
(Tip: You’ll find the full list of ingredients and measurements in the recipe card below.)
5 large butter croissants, preferably day-old, torn into chunks
6 large eggs
1 ½ cups milk (dairy or non-dairy)
1 cup shredded cheddar cheese
½ teaspoon salt
¼ teaspoon black pepper
Optional: ½ cup cooked crumbled sausage or sautéed vegetables
Directions
I start by lightly greasing a 9×13-inch baking dish.
Then, I scatter the torn croissant pieces evenly in the dish.
In a large mixing bowl, I whisk together the eggs, milk, salt, and pepper until well combined.
I stir in the shredded cheese and any extras I want to add—sausage or veggies are great options.
I pour the egg mixture evenly over the croissants, pressing down lightly to help them absorb the liquid.
After covering the dish, I refrigerate it overnight (or for at least 4 hours).
The next morning, I preheat the oven to 350°F (175°C).
I bake the casserole uncovered for 35–40 minutes, until the center is set and the top is golden.
I let it cool for 5–10 minutes before slicing and serving.
Servings and timing
This recipe makes 6 servings.
Prep Time: 10 minutes
Chill Time: Minimum 4 hours (overnight preferred)
Cook Time: 35–40 minutes
Total Time: 50 minutes (plus chilling)
Calories per serving: Approximately 310 kcal
Variations
I like switching things up depending on what I have in the fridge. Sometimes I add sautéed spinach, mushrooms, or diced bell peppers for extra flavor and color. If I want something meatier, I toss in cooked bacon or crumbled breakfast sausage. A mix of cheeses like mozzarella, Swiss, or pepper jack also works beautifully for different flavor profiles.
Storage/Reheating
To store leftovers, I cover the casserole or transfer slices to an airtight container and refrigerate for up to 3 days. When I’m ready to reheat, I warm individual portions in the microwave for about 1–2 minutes. For best results, I reheat larger portions in the oven at 325°F until heated through.
FAQs
How far in advance can I make this casserole?
I usually make it the night before, but I’ve prepared it up to 24 hours in advance without any issues. Just be sure to keep it covered and refrigerated.
Can I freeze the casserole?
Yes, I freeze it after baking. Once cooled, I wrap it tightly and freeze it for up to 2 months. To reheat, I thaw it overnight in the fridge and bake at 325°F until warm.
What can I use instead of croissants?
Day-old brioche or challah bread works really well if I don’t have croissants. The richness and texture are similar and hold up nicely with the egg mixture.
Can I make it dairy-free?
Definitely. I use a non-dairy milk like almond or oat, and swap the cheese for a plant-based version. The results are still creamy and delicious.
How do I know when the casserole is fully cooked?
I check that the center is set and no longer jiggles when I shake the dish lightly. A knife inserted in the middle should come out clean or just slightly moist.
Conclusion
This Overnight Croissant Breakfast Casserole has become one of my go-to recipes for a no-fuss, satisfying breakfast. Whether I’m feeding guests or just want something cozy for myself, it always delivers. The prep is minimal, the flavors are rich, and the results are always crowd-pleasing. I like that it makes mornings feel special without much work—just how breakfast should be.
Recipe:
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Overnight Croissant Breakfast Casserole
- Total Time: 50 minutes (plus chilling time)
- Yield: 6 servings
- Diet: Vegetarian
Description
A rich and comforting breakfast casserole made with buttery croissants, creamy eggs, and melted cheese. Perfect for make-ahead holiday mornings, brunches, or relaxed weekends.
Ingredients
5 large butter croissants, preferably day-old, torn into chunks
6 large eggs
1 ½ cups milk (dairy or non-dairy)
1 cup shredded cheddar cheese
½ teaspoon salt
¼ teaspoon black pepper
Optional: ½ cup cooked crumbled sausage or sautéed vegetables
Instructions
- Lightly grease a 9×13-inch baking dish.
- Scatter the torn croissant pieces evenly in the dish.
- In a large mixing bowl, whisk together the eggs, milk, salt, and pepper until well combined.
- Stir in the shredded cheese and any optional add-ins like sausage or vegetables.
- Pour the egg mixture evenly over the croissants, pressing down lightly to help them absorb the liquid.
- Cover the dish and refrigerate overnight or for at least 4 hours.
- Preheat the oven to 350°F (175°C).
- Bake the casserole uncovered for 35–40 minutes, until the center is set and the top is golden.
- Let the casserole cool for 5–10 minutes before slicing and serving.
Notes
Customize with different cheeses like Swiss or pepper jack for flavor variety.
Add sautéed spinach, mushrooms, or bell peppers for extra vegetables.
Store leftovers in an airtight container in the fridge for up to 3 days.
Reheat individual portions in the microwave or larger portions in the oven at 325°F.
Can be frozen after baking for up to 2 months. Thaw in fridge and reheat at 325°F.
Use brioche or challah as a substitute for croissants if needed.
Make it dairy-free by using non-dairy milk and plant-based cheese.
- Prep Time: 10 minutes
- Cook Time: 40 minutes
- Category: Breakfast
- Method: Baking
- Cuisine: American
Nutrition
- Serving Size: 1 slice (1/6 of casserole)
- Calories: 310
- Sugar: 3g
- Sodium: 450mg
- Fat: 20g
- Saturated Fat: 10g
- Unsaturated Fat: 8g
- Trans Fat: 0g
- Carbohydrates: 20g
- Fiber: 1g
- Protein: 13g
- Cholesterol: 215mg
