Overnight Breakfast Casserole: The Easiest Make-Ahead Brunch Ever

Last Updated on November 7, 2025 by Chef Josie

This Overnight Breakfast Casserole is the ultimate solution for stress-free mornings. Whether you’re hosting a holiday brunch, preparing for a busy family weekend, or planning a cozy Christmas morning breakfast, this dish delivers big flavor with minimal effort.

Loaded with eggs, cheese, bacon, bread cubes, and colorful vegetables, this casserole bakes up golden, fluffy, and irresistibly savory. The best part? You can assemble it the night before, no morning prep required. Just pop it in the oven, relax, and enjoy the delicious aroma filling your kitchen.

Perfect for feeding a crowd or meal-prepping for the week, this easy make-ahead breakfast casserole is hearty, comforting, and endlessly customizable.

Click to Access the Table of Contents:

Table of Contents

Print

Why You’ll Love This Overnight Breakfast Casserole

• Make-ahead convenience: Assemble it the night before for a no-stress breakfast.
• Perfect for feeding a crowd: Great for brunches, holidays, or weekends.
• Flavorful and filling: Packed with eggs, cheese, bacon, and fresh veggies.
• Customizable: Easily adapt with your favorite meats or vegetables.
• Family favorite: Loved by kids and adults alike.

Ingredients

• 6 large eggs
• 2 cups milk
• 4 cups cubed bread (day-old works best)
• 1½ cups shredded cheddar cheese
• 1 cup cooked bacon, crumbled
• ½ cup diced bell peppers
• ¼ cup chopped green onions
• ½ tsp salt
• ¼ tsp black pepper
• Optional: ½ tsp garlic powder or Italian seasoning

Instructions

1. Prepare the base: Grease a 9×13-inch baking dish and layer cubed bread evenly across the bottom.
2. Add the mix-ins: Sprinkle cooked bacon, bell peppers, green onions, and cheese evenly over the bread.
3. Whisk the eggs: In a large bowl, whisk together eggs, milk, salt, and seasonings.
4. Combine: Pour the egg mixture over the casserole, pressing gently to ensure the bread absorbs the liquid.
5. Refrigerate overnight: Cover tightly and chill for at least 8 hours.
6. Bake: Remove from fridge and let stand 20 minutes. Bake at 350°F (175°C) for 45–50 minutes, or until golden and set.
7. Serve: Cool slightly before slicing and serving warm.

Notes and Top Tips

• Use stale or toasted bread to prevent sogginess.
• For a healthier twist, use whole-grain bread and low-fat cheese.
• Add extra veggies like spinach, mushrooms, or zucchini for color and nutrients.
• Want a sweet option? Try a French toast breakfast casserole version with cinnamon and maple syrup instead of savory add-ins.

Serving Suggestions and Variations

This Overnight Breakfast Casserole is ideal for holiday brunches, potlucks, or weekend breakfasts. Serve it with fresh fruit, yogurt, or pastries for a complete spread.

Variations:

• French Toast Version: Use brioche or challah bread and add cinnamon, sugar, and maple syrup.
• Overnight Egg Casserole: Add spinach, mushrooms, and feta cheese for a Mediterranean flavor.
• Crockpot Breakfast Casserole: Layer ingredients in a slow cooker and cook on low for 6–7 hours.
• Vegetarian Brunch Casserole: Skip the meat and double up on colorful vegetables.

Storage and Reheating Tips

• Refrigerate: Store leftovers in an airtight container for up to 4 days.
• Freeze: Wrap portions tightly and freeze up to 2 months. Thaw overnight before reheating.
• Reheat: Microwave individual servings or warm in the oven at 325°F until heated through.
• Make ahead: Prep the night before and bake fresh for the best texture and flavor.

Why You’ll Make It Again

This Overnight Breakfast Casserole is a lifesaver for busy mornings and special occasions alike. It’s hearty, comforting, and simple to make, a guaranteed hit with family and guests every time.

With endless variations and make-ahead flexibility, it’s a recipe you’ll turn to again and again, whether for a festive Christmas brunch, a weekend family breakfast, or an easy meal prep solution for the week ahead.

FAQs

1. Can I make this casserole without refrigerating overnight?
Yes, you can bake it immediately after assembling, but overnight chilling enhances flavor and texture.

2. Can I use hashbrowns instead of bread?
Absolutely! Substitute 4 cups of thawed hashbrowns for a potato-based version.

3. Can I make this dairy-free?
Yes, use almond or oat milk and dairy-free cheese alternatives.

4. How do I keep the casserole from getting soggy?
Use day-old bread, reduce milk slightly, and avoid over-mixing the egg mixture.

For more delicious recipes follow me on :

Medium: @RecipesByJosie

Instagram: @RecipesByJosie

Pinterest: @RecipesByJosie