Grilled Cheese Breakfast Casserole

Start your morning off right with this warm and comforting Grilled Cheese Breakfast Casserole! This twist on a classic grilled cheese sandwich is baked into a savory, cheesy casserole that’s loaded with golden bread, gooey cheese, and fluffy eggs. It’s an easy crowd-pleaser perfect for weekend brunches, holiday mornings, or make-ahead meal prep.

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Why You’ll Love This Recipe
Easy to Make – Minimal prep and hands-off baking time.
Perfect for Groups – Great for feeding a hungry crowd.
Kid-Approved – Classic grilled cheese flavor with a fun breakfast twist.
Make-Ahead Friendly – Prep it the night before and bake in the morning.
Customizable – Add your favorite breakfast ingredients like veggies or cooked sausage.

Ingredients You’ll Need

For the Casserole:

• 1 loaf thick-cut white bread or sourdough, cut into 1-inch cubes
• 2 cups shredded cheddar cheese
• 1 cup shredded mozzarella cheese
• 6 large eggs
• 2 cups milk (whole or 2%)
• ½ cup heavy cream
• 1 tsp Dijon mustard
• ½ tsp garlic powder
• ½ tsp salt
• ¼ tsp black pepper
• 2 tbsp unsalted butter, melted

Optional Add-Ins:

• ½ cup cooked breakfast sausage or chopped beef bacon
• ½ cup sautéed spinach or mushrooms
• ¼ cup green onions or chives, chopped

For Garnish:

• Extra shredded cheese on top
• Chopped parsley or green onions

Tools You’ll Need

• Large mixing bowl
• 9×13-inch baking dish
• Whisk
• Measuring cups and spoons
• Foil or plastic wrap (if prepping ahead)

Step-by-Step Instructions

Step 1: Prep the Bread and Cheese

1. Cut bread into 1-inch cubes and let it sit out for a few hours to dry slightly, or toast lightly for a firmer texture.
2. Grease your baking dish with melted butter or nonstick spray.
3. Add half of the bread cubes to the bottom of the baking dish.
4. Sprinkle with half of the cheddar and mozzarella cheese.
5. Add any optional cooked add-ins like sausage or veggies.
6. Repeat with the remaining bread and cheese, layering them evenly.

Step 2: Make the Egg Mixture
7. In a large bowl, whisk together eggs, milk, cream, Dijon mustard, garlic powder, salt, and pepper until well combined.
8. Pour the egg mixture evenly over the layered bread and cheese in the dish.
9. Press down gently to help the bread absorb the liquid.

Step 3: Chill or Bake
10. For best results, cover the casserole and refrigerate for at least 1 hour or overnight. This allows the bread to soak up the custard.
11. If baking immediately, let it sit at room temperature for 15 minutes.

Step 4: Bake the Casserole
12. Preheat the oven to 350°F (175°C).
13. Uncover the casserole and sprinkle with extra cheese on top.
14. Bake for 40–45 minutes, or until the top is golden and the center is set.
15. Let it rest for 5–10 minutes before slicing.

Step 5: Garnish & Serve
16. Garnish with chopped parsley or green onions for a fresh finish.
17. Serve warm with fruit, salad, or a side of crispy potatoes.

Tips for the Best Breakfast Casserole
Use Day-Old Bread – Slightly stale bread holds its shape better and soaks up the egg mixture.
Add Veggies – Sautéed mushrooms, spinach, or bell peppers add nutrition and flavor.
Let It Rest – Resting after baking ensures clean slices and a perfect texture.
Double the Cheese – Extra cheese on top creates a golden, bubbly crust.

Serving Suggestions
Brunch Buffet – Serve with fresh fruit, hash browns, and coffee.
Holiday Morning – Prep the night before and bake fresh for Christmas or Easter breakfast.
Quick Lunch – Reheat slices and pair with soup or salad.
Meal Prep – Slice and store portions for a quick weekday breakfast.

How to Store & Reheat

Storing:
Refrigerate: Cover tightly or store in an airtight container for up to 4 days.

Freezing:
Freeze fully baked and cooled slices wrapped in foil or a freezer-safe container for up to 2 months.

Reheating:
Oven: Reheat at 350°F for 10–15 minutes.
Microwave: Heat slices in 30-second intervals until warmed through.

Frequently Asked Questions

1. Can I use a different kind of bread?
   Yes! Try brioche, French bread, or even whole grain for a heartier version.
2. Can I make it vegetarian?
   Definitely! Just skip the meat and load it with your favorite veggies.
3. Is it okay to use dairy-free alternatives?
   Yes, use plant-based milk and cheese alternatives, and a dairy-free creamer for the best texture.
4. Can I prep this the night before?
   Absolutely! Refrigerate overnight and bake fresh in the morning.

Final Thoughts
Grilled Cheese Breakfast Casserole is a warm, cheesy, and satisfying way to start your day. Whether you’re feeding a large group or just want something hearty and homemade, this casserole has all the familiar flavors of a grilled cheese sandwich packed into a cozy morning bake. It’s easy to customize, store, and serve—making it a breakfast winner every time.

Try it out and let me know what you think! Don’t forget to leave a review below and share your photos on Pinterest! I can’t wait to see how yours turns out.

Preparation Time: 15 minutes
Cooking Time: 45 minutes
Cuisine: American

Nutritional Information (Per Serving):
Calories: 420 | Protein: 18g | Carbohydrates: 30g | Fat: 26g | Fiber: 2g | Sodium: 520mg

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