Overnight Breakfast Casserole

This Overnight Breakfast Casserole is your new go-to for a stress-free, delicious morning meal. Made with layers of eggs, bread, cheese, and your choice of veggies or protein, it’s assembled the night before and baked fresh in the morning. Perfect for holidays, brunch parties, or meal prepping your week, this dish is hearty, customizable, and crowd-pleasing.

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Why You’ll Love This Recipe
Prep Ahead – Mix it up the night before, bake it fresh in the morning.
Feeds a Crowd – Great for family brunches, holidays, or potlucks.
Flexible Ingredients – Use what you have on hand.
Hearty & Filling – Packed with protein and flavor.
Freezer-Friendly – Easy to make in bulk and freeze.

Ingredients You’ll Need

• 8 slices of whole grain or sourdough bread, cubed
• 8 large eggs
• 2 cups milk (any kind—dairy or plant-based)
• 1½ cups shredded cheese (cheddar, mozzarella, or a blend)
• 1 tsp Dijon mustard (adds depth, optional)
• Salt and pepper to taste
• 1 tsp garlic powder
• ½ tsp paprika

Add-ins (choose your favorites):

• 1 cup cooked chicken or beef sausage, diced
• 1 bell pepper, diced
• ½ cup chopped spinach or kale
• ½ red onion, diced
• 1 cup mushrooms, sautéed
• 2 tbsp fresh parsley or green onions for garnish

Tools You’ll Need

• 9×13 inch (23×33 cm) baking dish
• Mixing bowls
• Whisk
• Plastic wrap or foil
• Spatula

Step-by-Step Instructions

Step 1: Assemble the Base

1. Grease a 9×13-inch baking dish.
2. Spread cubed bread evenly across the bottom.
3. Top with cooked protein, vegetables, and half the cheese.

Step 2: Make the Egg Mixture
4. In a mixing bowl, whisk together eggs, milk, Dijon mustard, garlic powder, paprika, salt, and pepper.
5. Pour the egg mixture evenly over the bread and toppings in the baking dish.
6. Press gently with a spatula so the bread soaks up the liquid.

Step 3: Chill Overnight
7. Cover the dish tightly with plastic wrap or foil.
8. Refrigerate overnight (at least 6 hours) to allow flavors to meld and the bread to absorb the liquid.

Step 4: Bake in the Morning
9. Preheat oven to 350°F (175°C).
10. Remove casserole from the fridge and uncover.
11. Sprinkle the remaining cheese over the top.
12. Bake for 45–50 minutes, or until the center is set and the top is golden brown.
13. Let rest for 5–10 minutes before slicing and serving.

Tips for the Best Breakfast Casserole
Use Stale Bread – It holds up better and soaks the eggs beautifully.
Add Protein – Sausage, shredded chicken, or meatballs work well.
Pre-Cook Veggies – Especially onions and mushrooms for better texture.
Let It Rest – Resting after baking helps slices hold together.
Make It Spicy – Add a pinch of chili flakes or diced jalapeños.

Serving Suggestions
With Fresh Fruit – A sweet and juicy side pairs perfectly.
With Yogurt & Granola – For a complete brunch table.
With Salsa or Hot Sauce – Adds a tangy or spicy kick.
With a Side Salad – Light greens balance the hearty casserole.
As Grab-and-Go Slices – Perfect for busy weekday breakfasts.

How to Store & Reheat

Store:
Refrigerate leftovers in an airtight container for up to 4 days.

Reheat:
Oven – Bake at 300°F (150°C) for 10–15 minutes.
Microwave – Heat individual slices for 1 minute.

Freeze:
Wrap individual slices or the whole casserole tightly and freeze for up to 2 months. Thaw in the fridge overnight and reheat before serving.

Frequently Asked Questions

1. Can I use gluten-free bread?
Yes, just make sure it’s slightly stale or toasted to avoid sogginess.

2. Can I make it dairy-free?
Use plant-based milk and dairy-free cheese alternatives.

3. Can I cook it right away instead of overnight?
You can, but the texture is better when it sits overnight.

4. Can I make mini versions?
Yes! Use a muffin tin and reduce the baking time to 20–25 minutes.

Final Thoughts

This Overnight Breakfast Casserole is the definition of convenience and comfort. It’s a no-fuss dish that tastes like you spent hours preparing it, and it’s endlessly adaptable to whatever ingredients you have on hand.

Make mornings easier—and tastier—by prepping this satisfying, savory bake the night before!

Preparation Time: 15 minutes
Chill Time: 6–12 hours
Baking Time: 50 minutes
Cuisine: American – Make-Ahead Brunch

Nutritional Information (Per Serving, 8 servings):
Calories: 290 | Protein: 17g | Carbohydrates: 20g | Fat: 16g | Fiber: 2g | Sugar: 4g | Sodium: 420mg

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