Overnight Breakfast Casserole

Want to wake up to a hot, hearty breakfast without morning stress? This Overnight Breakfast Casserole is the ultimate make-ahead dish. Loaded with eggs, bread, veggies, and melty cheese, it’s a savory, comforting breakfast that feeds a crowd with zero fuss in the morning. Just prep it the night before, refrigerate, and bake when you’re ready to enjoy!

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Why You’ll Love This Recipe
Make-Ahead Magic – Assemble it at night and bake it fresh in the morning.
Hearty & Filling – Packed with protein, veggies, and whole grains.
Family-Friendly – Everyone loves a slice of this cheesy bake.
Customizable – Add your favorite veggies or swap in cooked meats.
Perfect for Brunch – Ideal for holidays, weekends, or feeding guests.

Ingredients You’ll Need

For the Casserole Base:

• 6 large eggs
• 2 cups milk (dairy or plant-based)
• 1 tsp Dijon mustard (adds depth)
• Salt and black pepper, to taste
• 6–8 slices whole grain or sourdough bread, cubed
• 1 ½ cups shredded cheese (cheddar, mozzarella, or your favorite blend)
• 1 cup cooked and crumbled chicken sausage or ground beef (optional)
• 1 bell pepper, diced
• 1 cup spinach or kale, chopped
• ½ cup red onion, finely diced
• Optional: ½ tsp garlic powder or Italian seasoning

For Topping (optional):

• ¼ cup grated Parmesan cheese
• Fresh chives or parsley for garnish
• Sliced cherry tomatoes

Tools You’ll Need
9×13-inch baking dish
Large mixing bowl
Whisk
Foil or plastic wrap
Spatula
Refrigerator & oven

Step-by-Step Instructions

Step 1: Prepare the Ingredients

1. Lightly grease your baking dish.
2. Dice the vegetables and cube the bread into bite-sized pieces.
3. If using meat, cook and crumble it, then set aside to cool.

Step 2: Make the Egg Mixture

1. In a large bowl, whisk together eggs, milk, Dijon mustard, salt, pepper, and optional garlic or herbs.
2. Whisk until well combined and smooth.

Step 3: Assemble the Casserole

1. Spread half of the bread cubes in the bottom of the baking dish.
2. Layer with half the veggies, meat (if using), and cheese.
3. Repeat the layers with remaining bread, veggies, meat, and cheese.
4. Pour the egg mixture evenly over the top, pressing down gently so all the bread is soaked.

Step 4: Cover and Chill Overnight

1. Cover the dish tightly with foil or plastic wrap.
2. Refrigerate for at least 6 hours or overnight.

Step 5: Bake in the Morning

1. Preheat your oven to 175°C (350°F).
2. Remove casserole from the fridge and let sit at room temp for 20–30 minutes.
3. Uncover and sprinkle with Parmesan and optional tomato slices.
4. Bake for 45–50 minutes until the center is set and top is golden.
5. Let rest for 5–10 minutes before slicing.

Tips for the Best Breakfast Casserole
Use Sturdy Bread – Day-old sourdough or whole grain bread works best.
Don’t Skip Soaking – Overnight chilling lets the bread absorb all the flavor.
Prep in Advance – You can prep 1–2 days ahead and bake fresh.
Balance Textures – Mix soft veggies with crunchy toppings or seeds.
Let It Rest – This helps the casserole hold together for clean slices.

Serving Suggestions
With Fruit Salad – Brighten up the plate with fresh berries or citrus.
With Yogurt Parfaits – A creamy and sweet contrast.
With Coffee or Tea – A warm drink is the perfect pairing.
For Meal Prep – Portion and reheat for easy weekday breakfasts.
As a Brunch Main – Add muffins, juice, or smoothies on the side.

How to Store & Reheat

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

Freeze:
Wrap individual portions and freeze for up to 2 months. Thaw overnight in the fridge.

Reheat:
Oven: 160°C (325°F) for 15 minutes or until warmed through.
Microwave: 1–2 minutes per slice, depending on thickness.

Frequently Asked Questions

1. Can I make this without meat?
   Absolutely! Just load up on extra veggies like mushrooms or zucchini.
2. What’s the best bread to use?
   Sourdough, French bread, or multigrain loaves hold up best.
3. Can I use egg whites instead of whole eggs?
   Yes—use 8–10 egg whites or a combo of whole eggs and whites.
4. How do I keep it from being soggy?
   Make sure the bread is slightly dry, and don’t overdo the liquid.

Final Thoughts
This Overnight Breakfast Casserole makes mornings easier and tastier. Whether you’re hosting brunch, prepping for the week, or just want a warm, comforting meal waiting when you wake up—this dish delivers every time. Fluffy, cheesy, hearty, and endlessly customizable—it’s a breakfast winner!

Try it this weekend and let the oven do the work while you enjoy the morning.

Prep Time: 15 minutes
Chill Time: Overnight (6+ hours)
Bake Time: 50 minutes
Total Time: About 1 hour (plus chilling)
Cuisine: American

Nutritional Information (Per Serving, 1 of 8):
Calories: 310 | Protein: 17g | Carbs: 24g | Fat: 18g | Fiber: 3g | Sodium: 520mg

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