Overnight Croissant Breakfast Casserole
This Overnight Croissant Breakfast Casserole is buttery, savory, and perfect for stress-free mornings. Prep it the night before, then bake and enjoy! Loaded with sausage, cheese, and flaky croissants for a cozy, crowd-pleasing breakfast or brunch.
Ingredients
- 6 large butter croissants preferably day-old
- 1 lb breakfast sausage or bacon/ham
- 1 ½ cups shredded sharp cheddar cheese
- 1 cup shredded mozzarella cheese
- 8 large eggs
- 2 cups whole milk
- ½ cup heavy cream
- 1 tsp Dijon mustard
- ½ tsp garlic powder
- ½ tsp onion powder
- Salt and pepper to taste
- 2 tbsp chopped chives or green onions optional, for garnish
Instructions
- Brown the Sausage: In a skillet over medium heat, cook your sausage until fully browned. Drain excess fat and set aside to cool.
- Tear the Croissants: Roughly tear the croissants into bite-sized chunks and layer them in a greased 9x13-inch baking dish.
- Add the Sausage & Cheese: Sprinkle the cooked sausage evenly over the croissants, followed by the cheddar and mozzarella cheeses.
- Make the Egg Mixture: In a large bowl, whisk together the eggs, milk, cream, Dijon, garlic powder, onion powder, salt, and pepper.
- Pour the Custard: Slowly pour the egg mixture over the croissant mixture, making sure everything is evenly coated.
- Cover & Chill: Cover the dish tightly with plastic wrap or foil and refrigerate overnight (at least 8 hours).
- Bake in the Morning: Preheat oven to 350°F (175°C). Remove the casserole from the fridge and let it sit at room temp for 20 minutes. Bake uncovered for 45–50 minutes until golden and set in the middle.
- Garnish & Serve: Let cool for 5 minutes, sprinkle with fresh chives, and serve warm.
Notes
Overnight Croissant Breakfast Casserole – Helpful Tips
✅ Cooking Tips & Techniques
• Use day-old or slightly stale croissants—they soak up the custard better without falling apart.
• Tear croissants into large chunks for a rustic look and better texture contrast once baked.
• Whisk the custard mixture thoroughly to ensure the eggs, milk, and seasonings are evenly incorporated.
• Let the casserole sit overnight (8–12 hours) in the fridge so every bite gets soaked in that savory custard.
• Bake uncovered for a golden, crisp top—tent with foil halfway through if it browns too quickly. ✅ Serving Suggestions
• Serve warm with a side of fresh fruit or citrus salad to balance the richness.
• A dollop of creamy Dijon mustard or hot sauce on the side adds zing.
• Pair with a simple arugula or mixed greens salad tossed in vinaigrette for a brunch-style plate.
• Great with freshly brewed coffee or mimosas—brunch done right! ✅ Make-Ahead & Storage
• Assemble the casserole the night before and refrigerate. Just pop it in the oven in the morning—perfect for holidays or weekend brunch.
• Leftovers keep well in the fridge for up to 4 days. Reheat individual portions in the microwave or oven.
• You can freeze the fully baked casserole (cooled and wrapped) for up to 2 months. Thaw overnight and reheat at 350°F until warmed through. ✅ Tasty Variations to Try
• Spinach & Feta – Add sautéed spinach and crumbled feta cheese for a Mediterranean twist.
• Bacon Lover’s Edition – Use cooked, crumbled bacon instead of sausage or ham.
• Southwest Style – Mix in diced green chiles, pepper jack cheese, and a dash of cumin.
• Mushroom & Swiss – Sauté mushrooms with garlic and thyme, then layer them in with shredded Swiss cheese.
• Sweet & Savory – Add a hint of maple syrup to the custard and a sprinkle of sharp cheddar for that salty-sweet combo.
• Use day-old or slightly stale croissants—they soak up the custard better without falling apart.
• Tear croissants into large chunks for a rustic look and better texture contrast once baked.
• Whisk the custard mixture thoroughly to ensure the eggs, milk, and seasonings are evenly incorporated.
• Let the casserole sit overnight (8–12 hours) in the fridge so every bite gets soaked in that savory custard.
• Bake uncovered for a golden, crisp top—tent with foil halfway through if it browns too quickly. ✅ Serving Suggestions
• Serve warm with a side of fresh fruit or citrus salad to balance the richness.
• A dollop of creamy Dijon mustard or hot sauce on the side adds zing.
• Pair with a simple arugula or mixed greens salad tossed in vinaigrette for a brunch-style plate.
• Great with freshly brewed coffee or mimosas—brunch done right! ✅ Make-Ahead & Storage
• Assemble the casserole the night before and refrigerate. Just pop it in the oven in the morning—perfect for holidays or weekend brunch.
• Leftovers keep well in the fridge for up to 4 days. Reheat individual portions in the microwave or oven.
• You can freeze the fully baked casserole (cooled and wrapped) for up to 2 months. Thaw overnight and reheat at 350°F until warmed through. ✅ Tasty Variations to Try
• Spinach & Feta – Add sautéed spinach and crumbled feta cheese for a Mediterranean twist.
• Bacon Lover’s Edition – Use cooked, crumbled bacon instead of sausage or ham.
• Southwest Style – Mix in diced green chiles, pepper jack cheese, and a dash of cumin.
• Mushroom & Swiss – Sauté mushrooms with garlic and thyme, then layer them in with shredded Swiss cheese.
• Sweet & Savory – Add a hint of maple syrup to the custard and a sprinkle of sharp cheddar for that salty-sweet combo.