Easy Make-Ahead Breakfast Casserole Recipe for Busy Mornings

This Easy Make-Ahead Breakfast Casserole is a lifesaver for busy mornings when you need something hearty, healthy, and ready to go. With just 20 minutes of prep time, you can assemble this delicious dish the night before. In the morning, pop it into the oven, and 45 minutes later, you’ll have a warm, cheesy, protein-packed breakfast ready to fuel your day.

What I love most? This easy breakfast casserole puts your mornings on autopilot. It saves time, reduces stress, and is perfect for feeding a hungry crowd. Whether you’re meal prepping for the week or hosting brunch, this recipe is one you’ll come back to again and again.

Why This Easy Make-Ahead Breakfast Casserole Is a Game-Changer

• Time-saving: Prep everything the night before, so your morning is totally hands-off.
• Make-ahead flexibility: Chill the assembled casserole in your fridge for up to 24 hours or freeze it for even longer.
• One-dish magic: Less mess, fewer dishes. Bake directly in your serving dish.
• Customizable: Swap veggies, cheese, or protein to use up what’s in your fridge.
• Perfect for meal prep: Leftovers reheat beautifully for busy weekday mornings.

Equipment You’ll Need for This Easy Make-Ahead Breakfast Casserole

This recipe doesn’t require any fancy gadgets—just reliable kitchen basics:

• 9×13-inch casserole dish: Make sure it’s oven-safe and large enough to hold all ingredients.
• Large skillet: For browning the turkey sausage and sautéing the veggies.
• Mixing bowl: A medium-sized bowl works perfectly for whisking the egg mixture.
• Foil or plastic wrap: Essential for covering the dish during refrigeration.

If you don’t have a 9×13-inch pan, a 3–4-quart ovenproof dish will do the job just as well.

Simple Ingredients for Easy Make-Ahead Breakfast Casserole

What makes this homemade breakfast casserole shine is its fresh, wholesome ingredients. Here are a few highlights:

• Crusty bread: Day-old bread works best because it soaks up all the eggy goodness without getting soggy.
• Turkey sausage: A lean protein option that pairs perfectly with the savory veggies.
• Fresh vegetables: Bell peppers, mushrooms, and spinach add color, texture, and nutrients.
• Cheddar cheese: Melty, gooey, and absolutely necessary. Feel free to use your favorite shredded cheese blend.

Pro tip: Keep pre-chopped veggies or bagged spinach on hand to shave off even more prep time!

Easy Make-Ahead Breakfast Casserole Recipe Details

• Servings: Serves 12
• Prep Time: 20 minutes
• Cook Time: 45 minutes
• Total Time: 1 hour, 30 minutes

Easy Make-Ahead Breakfast Casserole Ingredients

• 4 cups (175g or 6 oz) cubes of crusty bread
• 1 teaspoon olive oil
• 1 pound ground turkey sausage, casings removed
• 1 teaspoon dried rosemary or Italian seasoning (optional)
• 3/4 cup (100g) chopped yellow onion (1/2 of a large onion)
• 2 garlic cloves, minced
• 2 cups (275g or 9–10 oz) chopped bell peppers
• 1 cup (100g or 3 oz) sliced mushrooms
• 1 cup roughly chopped fresh spinach
• 12 large eggs
• 1/4 teaspoon salt
• 1/8 teaspoon freshly ground black pepper
• 2/3 cup (160ml) milk or half-and-half
• 1 cup (100g or 3.5 oz) shredded cheddar cheese
• Optional garnish: green onion and/or chopped parsley

How to Make Easy Make-Ahead Breakfast Casserole

1. Grease a 9×13-inch dish and spread the bread cubes in an even layer.
2. In a skillet, heat olive oil over medium heat. Brown the turkey sausage, breaking it into small pieces, and stir in rosemary or Italian seasoning if using.
3. Add onions, garlic, bell peppers, mushrooms, and spinach to the pan. Sauté until softened, about 5–6 minutes.
4. Distribute the sausage and veggie mixture evenly over the bread layer in the dish.
5. In a mixing bowl, whisk together eggs, salt, pepper, milk, and cheddar cheese. Pour this over the sausage and veggie mixture.
6. Cover the casserole tightly with plastic wrap or foil and refrigerate for at least 30 minutes, up to 24 hours.
7. When ready to bake, preheat your oven to 375°F (191°C). Allow the casserole to sit at room temperature for 10–15 minutes while the oven heats.
8. Bake uncovered for 40–45 minutes until golden brown, and a toothpick inserted in the center comes out clean.
9. Let the casserole cool for 10 minutes before slicing and serving. Garnish with green onion or parsley, if desired.

My Go-To Tips for Easy Make-Ahead Breakfast Casserole

• Use slightly stale bread for better texture—it won’t get mushy when mixed with the eggs.
• Make it vegetarian by skipping the sausage and adding extra veggies like zucchini or broccoli.
• Want a gluten-free version? Use gluten-free bread or cubed potatoes instead.
• Be sure to tightly cover the casserole before refrigerating to prevent it from drying out overnight.
• For a super crispy topping, sprinkle with an extra handful of shredded cheddar about halfway through baking.

Easy Make-Ahead Breakfast Casserole FAQs

Can I freeze this casserole?

Absolutely! Freeze it either unbaked or after baking. For an unbaked casserole, assemble as directed, wrap tightly, and freeze for up to 3 months. Thaw overnight in the fridge before baking.

Can I use a different type of sausage?

Yes! Ground pork sausage, chicken sausage, or even vegetarian sausage crumbles would work well in this recipe.

How do I reheat leftovers?

Portion out slices and microwave for 1-2 minutes until heated through. For larger amounts, cover the dish with foil and reheat in a 350°F oven for 15 minutes.

Your mornings just got easier with this amazing Easy Make-Ahead Breakfast Casserole. Let me know in the comments—what other quick breakfasts do you swear by?