Overnight Croissant Breakfast Casserole Bake with Gravy

Start your day on a delicious note with this indulgent Overnight Croissant Breakfast Casserole Bake with Gravy. Made with buttery croissants, savory breakfast sausage, and a rich egg custard, this dish is perfect for feeding a crowd or enjoying a cozy morning with the family. Plus, with a creamy homemade gravy to top it off, it’s a breakfast sensation that will have everyone coming back for seconds. Let’s dive into the details and learn how to make this mouthwatering dish that’s sure to become a breakfast favorite!


  • 1 tablespoon olive oil
  • 1 small onion, peeled and chopped
  • 1 pound roll breakfast sausage, mild flavor
  • 4 large butter croissants or 8 small croissants
  • 1 cup shredded cheddar cheese
  • 6 large eggs
  • ½ cup heavy whipping cream
  • 3 cups milk (whole milk recommended), divided
  • ½ teaspoon dry mustard powder
  • ½ teaspoon salt (plus additional for the gravy to taste)
  • ½ teaspoon black pepper (plus additional for the gravy to taste)
  • ¼ teaspoon paprika
  • ¼ teaspoon garlic powder
  • 2 tablespoons butter
  • 3 tablespoons all-purpose flour


1. Sauté the Aromatics: Heat olive oil in a large skillet over medium heat. Sauté chopped onions until softened and translucent. Add the breakfast sausage, crumble, and cook until browned. Drain the fat and reserve for gravy.

2. Prep the Casserole: In a large bowl, combine the cooked sausage and onions, torn croissants, and shredded cheese. Transfer the mixture to a greased 9×13-inch glass baking dish.

3. Make the Custard: In a medium mixing bowl, whisk together eggs, heavy whipping cream, ½ cup of milk, dry mustard powder, salt, pepper, paprika, and garlic powder. Pour the mixture over croissants and sausage in the baking dish.

4. Refrigerate Overnight: Cover the baking dish with plastic wrap and refrigerate overnight or for 8 hours to allow the flavors to meld and the croissants to soak up the custard.

5. Bake the Casserole: Preheat the oven to 350°F. Remove the casserole from the refrigerator and bake at 350°F for 35-45 minutes until golden brown and set.

6. Prepare the Gravy: Meanwhile, in a saucepan, melt butter and 1 tablespoon of reserved sausage fat over medium heat. Add flour and whisk until combined. Cook for 1 minute. Slowly add the remaining 2 ½ cups of milk, whisking well between each addition until smooth. Simmer on low heat for 2-3 minutes until thickened. Season with salt and pepper to taste.

7. Serve and Enjoy: Slice the casserole and serve with gravy on the side or ladled over each slice for a decadent breakfast experience.

Nutritional Information:

  • Prep Time: 30 minutes
  • Cooking Time: 45 minutes
  • Total Time: 1 hour 30 minutes
  • Servings: 12
  • Calories per Serving: (Calories will vary based on specific ingredients and portion sizes)

Serving and Storage Tips:

  1. Serving Suggestions: Serve slices of the croissant breakfast casserole with a dollop of the homemade gravy on top for a delightful breakfast or brunch. Pair it with fresh fruit salad or roasted potatoes to complement the flavors.
  2. Individual Portions: Cut the casserole into individual servings before storing or serving for easy portioning. This makes it convenient for meal prep or serving a crowd.
  3. Make-Ahead Option: Prepare the casserole up to the point of baking, cover it tightly, and refrigerate overnight. When ready to serve, simply bake according to the recipe instructions. Leftover baked casserole can also be stored and reheated for future meals.
  4. Storage: Store any leftover baked casserole in an airtight container in the refrigerator for up to 3-4 days. Reheat individual portions in the microwave or oven until warmed through.
  5. Freezing: You can freeze unbaked assembled casseroles for future use. Wrap the assembled casserole tightly with plastic wrap and aluminum foil, then freeze for up to 1-2 months. Thaw overnight in the refrigerator before baking as directed.


  1. Sweet and Savory Twist: Add a touch of sweetness to the casserole by incorporating slices of cooked apples or pears between the layers of croissants and sausage. Sprinkle cinnamon sugar on top for an extra burst of flavor.
  2. Vegetarian Option: Replace the breakfast sausage with sautéed vegetables such as bell peppers, mushrooms, and spinach for a hearty vegetarian version of the casserole. Add extra cheese for richness.
  3. Tex-Mex Flavors: Infuse the casserole with Tex-Mex flair by using spicy chorizo sausage, adding diced green chilies, and topping with salsa and sliced jalapeños. Serve with a side of avocado slices and sour cream for a complete meal.
  4. French-Inspired Variation: For a French-inspired twist, use ham and Gruyère cheese instead of sausage and cheddar. Add a pinch of nutmeg to the custard mixture for a classic flavor combination.
  5. Breakfast Sandwich Casserole: Layer croissant halves with cooked bacon or ham, scrambled eggs, and cheese to create a breakfast sandwich-inspired casserole. Top with a second layer of croissants and custard mixture before baking.
  6. Herb and Cheese Upgrade: Enhance the flavor profile of the casserole by adding chopped fresh herbs such as parsley, thyme, or chives to the custard mixture. Mix in additional cheese varieties such as Swiss or Monterey Jack for a cheesy indulgence.
  7. Low-Carb Option: For a lower-carb alternative, substitute croissants with slices of low-carb bread or cauliflower florets. Adjust the baking time as needed to ensure the casserole is cooked through.
  8. Fruity Delight: Incorporate dried fruit such as cranberries, apricots, or raisins into the casserole for a touch of sweetness and texture contrast. Soak the dried fruit in warm water or orange juice before adding to the dish.
  9. Overnight French Toast Casserole: Transform the croissant casserole into a decadent French toast bake by soaking the croissants in a mixture of eggs, milk, vanilla extract, and cinnamon overnight. Bake until golden and serve with maple syrup and fresh berries.
  10. Gluten-Free Option: Use gluten-free croissants or bread and ensure all other ingredients are gluten-free to accommodate individuals with gluten sensitivities or dietary restrictions. Adjust seasonings and flavors as needed.


  1. Can I Use Pre-made Gravy Instead of Making it from Scratch? Yes, pre-made gravy can be used as a time-saving option. Simply heat and serve alongside the casserole.
  2. Can I Use Turkey Sausage Instead of Pork Sausage? Absolutely! Turkey sausage can be substituted for pork sausage for a lighter option.
  3. Can I Freeze Leftover Gravy? Yes, leftover gravy can be frozen in an airtight container for up to 2-3 months. Thaw in the refrigerator before reheating.
  4. Can I Add Vegetables to the Casserole? Yes, feel free to add vegetables such as spinach, bell peppers, or mushrooms to the casserole for added flavor and nutrition.
  5. How Do I Prevent the Croissants from Getting Soggy? To prevent soggy croissants, ensure they are thoroughly dried before assembling the casserole. You can lightly toast them or leave them out to air dry for a few hours.
  6. Can I Make This Casserole in Advance for a Special Occasion? Yes, this casserole is perfect for making ahead. Prepare it the night before, refrigerate, and bake it in the morning for a stress-free breakfast.
  7. Can I Substitute Half-and-Half for the Heavy Whipping Cream? Yes, you can substitute half-and-half for the heavy whipping cream if you prefer a lighter texture.
  8. How Do I Know When the Casserole Is Done Baking? The casserole is done when the top is golden brown and the center is set. You can test for doneness by inserting a knife into the center – it should come out clean.
  9. Can I Add Cheese to the Gravy for Extra Flavor? Absolutely! Feel free to stir in shredded cheese such as cheddar or Gruyère to the gravy for added richness and flavor.
  10. What Can I Serve Alongside This Casserole for Brunch? This casserole pairs well with a variety of brunch dishes such as fresh fruit salad, breakfast potatoes, or a green salad with vinaigrette dressing.

With its buttery croissants, savory sausage, and creamy custard, this Overnight Croissant Breakfast Casserole Bake with Gravy is a breakfast masterpiece that’s sure to impress. Whether you’re hosting a brunch gathering or simply looking to elevate your morning routine, this dish delivers on flavor and comfort in every bite. So, set your alarm early and treat yourself to a breakfast sensation that will have you looking forward to waking up in the morning!