Overnight Breakfast Casserole

A Cozy Morning Starts the Night Before

Mornings can be hectic, but that doesn’t mean breakfast has to suffer. Imagine waking up to the aroma of a warm, cheesy, and satisfying casserole—ready to be enjoyed with minimal effort. That’s the magic of an overnight breakfast casserole!

Perfect for busy weekdays, holiday brunches, or meal prep, this dish brings together classic breakfast flavors in one delicious bite. Whether you’re feeding a crowd for Christmas morning, preparing for a weekend getaway, or just want a no-fuss breakfast solution, this recipe has you covered.

What makes this dish even better? It’s fully customizable! You can switch up the ingredients based on what you have on hand or your family’s preferences. Plus, assembling it the night before means you can enjoy a slow, stress-free morning while the oven does the work.

Why You’ll Love It

• Time-Saving – Prep everything the night before and simply bake in the morning. No morning rush!
• Packed with Flavor – A delicious mix of eggs, cheese, sausage, and bread creates a savory, satisfying bite.
• Great for Meal Prep – Make a big batch and store leftovers in the fridge for quick breakfasts all week.
• Customizable – Swap out the meats, veggies, or cheeses to suit your taste. You can even make it vegetarian!
• Perfect for Gatherings – Ideal for holiday mornings, brunch parties, or feeding overnight guests without the hassle.

Ingredient List

Here’s what you’ll need to make the ultimate overnight breakfast casserole:

For the Base:

• 1 loaf of French bread or sourdough, cubed (about 6-8 cups)
• 1 pound breakfast sausage (or bacon/ham), cooked and crumbled
• 1 cup diced bell peppers (any color)
• ½ cup diced onion
• 1 cup shredded cheddar cheese
• ½ cup shredded mozzarella cheese

For the Egg Mixture:

• 8 large eggs
• 2 cups whole milk (or half-and-half for creamier texture)
• ½ teaspoon salt
• ½ teaspoon black pepper
• ½ teaspoon garlic powder
• ½ teaspoon smoked paprika (optional, for added depth of flavor)

Want to make it extra special? Add in extras like spinach, mushrooms, or even a dash of hot sauce for a little kick.

Kitchen Tools Needed

To make this casserole, you’ll need a few essential kitchen tools:

• 9×13-inch baking dish – To hold and bake the casserole.
• Large mixing bowl – For whisking together the egg mixture.
• Whisk – Helps blend eggs, milk, and seasonings smoothly.
• Cutting board and knife – For dicing vegetables and bread.
• Skillet – To cook the sausage and soften the veggies.
• Measuring cups and spoons – For accurate ingredient measurements.
• Plastic wrap or foil – To cover and refrigerate the casserole overnight.

Instructions

Follow these simple steps to prepare your overnight breakfast casserole:

Step 1: Prepare the Bread and Sausage

• Cut the bread into cubes and spread them evenly in the greased 9×13-inch baking dish.
• Cook the breakfast sausage in a skillet over medium heat until browned. Drain any excess grease.
• Sprinkle the cooked sausage evenly over the bread cubes.

Step 2: Add the Vegetables and Cheese

• Dice the bell peppers and onions, then sauté them in the same skillet for about 3-4 minutes until slightly softened.
• Spread the veggies over the sausage and bread in the baking dish.
• Sprinkle both cheeses evenly over the top.

Step 3: Mix the Egg Mixture

• In a large mixing bowl, whisk together the eggs, milk, salt, black pepper, garlic powder, and smoked paprika.
• Pour the egg mixture evenly over the casserole, ensuring all the bread is soaked.

Step 4: Refrigerate Overnight

• Cover the casserole tightly with plastic wrap or foil.
• Place in the refrigerator for at least 6 hours or overnight to allow the flavors to meld.

Step 5: Bake and Serve

• Preheat the oven to 350°F (175°C).
• Remove the casserole from the refrigerator and let it sit at room temperature for 15-20 minutes.
• Bake uncovered for 45-50 minutes, or until the eggs are set and the top is golden brown.
• Let it cool for a few minutes before slicing and serving.

Ingredient Substitutions and Variations

Substitutions

• Bread – Use gluten-free bread or whole wheat for a healthier twist.
• Dairy-Free – Replace milk with almond, oat, or coconut milk, and use dairy-free cheese.
• Meat – Swap sausage for turkey sausage, chorizo, or even plant-based crumbles.
• Vegetables – Use zucchini, mushrooms, or spinach instead of peppers and onions.

Variations

• Mexican Style – Add diced jalapeños, black beans, and top with salsa.
• Mediterranean Twist – Use feta cheese, sun-dried tomatoes, and olives.
• Loaded Veggie – Include tomatoes, mushrooms, and spinach for a veggie-packed version.
• Spicy Kick – Mix in red pepper flakes or hot sauce for heat lovers.

Serving Suggestions

• With Fresh Fruit – A side of mixed berries or orange slices balances the richness.
• Avocado Slices – Creamy avocado pairs well with the savory flavors.
• Side of Toast – If you love extra carbs, serve with buttered toast or biscuits.
• Drizzle of Hot Sauce – Add a little spice with Sriracha or Tabasco.
• Glass of Fresh Juice – Orange juice or a smoothie makes a refreshing pairing.

Storage and Reheating Instructions

• Refrigerate – Store leftovers in an airtight container for up to 4 days.
• Freeze – Freeze individual slices wrapped in plastic wrap for up to 2 months.
• Reheat – Warm in the oven at 350°F for 10-15 minutes or microwave for 1-2 minutes.

FAQ

1. Can I make this casserole without bread?
Yes! Substitute with diced potatoes or hash browns for a gluten-free option.

2. Can I prepare this more than a night in advance?
You can prep it up to 24 hours ahead, but any longer may cause sogginess.

3. What if my casserole is too soggy?
Ensure you’re using stale bread and not adding too much liquid.

4. Can I bake it right away instead of refrigerating overnight?
Yes, but letting it sit enhances the flavors.

5. How can I make it vegetarian?
Simply skip the meat and add extra veggies.

6. Can I use egg substitutes?
Yes, try a mixture of flaxseed or an egg replacement product.

7. Can I add more cheese?
Absolutely! Add as much as you like for an extra cheesy casserole.

8. Can I make this in a slow cooker?
Yes! Cook on low for 6-8 hours or high for 3-4 hours.

Enjoy your easy, stress-free mornings with this delicious overnight breakfast casserole!

Did you try this recipe? Let me know in the comments how it turned out!

Don’t forget to share your photos on Instagram and tag me (@tasiahub_) or use the hashtag (#tasiahub). I’d love to see your creations!