Easy Overnight Everything Bagel Breakfast Casserole

This overnight everything bagel breakfast casserole is the perfect dish for slow, cozy mornings when you want something hearty but don’t want to spend your whole morning in the kitchen. You assemble it the night before using gluten free bagel cubes, an easy egg mixture, bacon, veggies, and cheese, then bake it until beautifully golden brown while the coffee brews. It’s a warm, savory bagel breakfast casserole recipe the whole family will love.

I rotate through a handful of breakfast casserole recipes when hosting or prepping for the holidays, and this one always gets a ton of requests. It has everything you love in a classic egg bake but layered with bagel seasoning, cheese, sautéed veggies, and crispy bacon. It’s like your favorite everything bagel with schmear… baked into casserole form.

If you’re planning a bigger spread for Christmas morning, you can pair this with cinnamon roll baked oatmeal, overnight french toast casserole, sheet pan pancakes, breakfast sliders, a fruit salad, or anything sweet to balance the savory. It’s also a reliable option for brunch hosting. Just assemble it ahead, let it come to room temperature, and bake while you enjoy the morning. 

Looking for more make ahead savory breakfast casseroles or egg dishes? Try this cottage cheese egg casserole, Christmas Morning breakfast casserole or these kale & mushroom egg bites.

Why You'll Love This Recipe

• Easy make ahead recipe. This overnight bagel breakfast casserole is a true make-ahead recipe, allowing you to assemble it the night before so you can enjoy a calm, easy morning.
• Satisfying and flavorful. Thanks to everything bagel seasoning, crispy bacon, and cheese, it’s packed with savory flavor combinations that taste like a bakery-style bagel in casserole form.
• It’s a simple, beginner-friendly egg bake that serves a crowd, adapts easily to different vegetables and cheeses, and is always a family favorite for holidays or weekend brunch.

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Everything Bagel Casserole Ingredients & Tested Substitutions

• Gluten-free everything bagels. Cut into bagel cubes to form the base of your bagel casserole. Use regular everything bagels if gluten-free isn’t required, or try sesame or plain bagels for different flavor combinations.
• Eggs. The foundation of the egg mixture that binds the casserole. You can enrich it with mozzarella cheese, cheddar cheese, or even a little gruyere cheese for added richness.
• Milk. You can choose whole milk, skim milk or non-dairy milk.
• Cottage cheese. Creates a creamy, protein-packed egg mixture. Swap with ricotta or add in shredded swiss cheese or cheddar cheese for a more traditional breakfast casserole flavor.
• Feta cheese. Adds tangy, salty contrast. For a milder flavor, substitute mozzarella, cheddar cheese, or gruyere cheese.
• Everything bagel seasoning. Everything bagel seasoning is essential for that classic bagel flavor. You can enhance it with kosher salt, garlic powder, or black pepper. Stir in red onion, green onions, or red bell pepper for more depth.
• Turkey bacon. I like to use turkey bacon but you can use regular bacon if you like or omit it for a vegetarian friendly option.
• Scallions/Green onion. Add brightness and fresh flavor. Substitute chives or fold in sautéed red onion for a sweeter finish.

Optional Add Ins

• Chunks of cream cheese for classic schmear-style pockets.
• Cheddar cheese, gruyere cheese, or swiss cheese for melty richness.
• Red onion, red bell pepper, or mushrooms sautéed over medium-high heat.

Everything Bagel Casserole Step by Step Instructions

1. Prepare the baking dish. Coat your baking dish with cooking spray and preheat oven to 350° Fahrenheit if baking right away.

2. Add the bagels. Add the bagel cubes to the dish, spreading them into an even layer.

3. Whisk the egg mixture. In a large bowl, whisk together the eggs, milk, cottage cheese, feta crumbles, scallions, everything bagel seasoning, kosher salt, and black pepper until smooth.

4. Pour over the casserole. Slowly pour the egg mixture over the bagel cubes, gently pressing down so everything begins to soak.

5. Add optional toppings. If using bacon, additional cheese, red onion, spinach or bell pepper, sprinkle them on top now.

6. Refrigerate overnight. Cover and refrigerate for at least 4 hours or overnight if you're making this ahead of time.

7. Bring to room temperature. Let the casserole sit at room temperature for 20 to 30 minutes while you preheat the oven to 350°F.

8. Bake. Bake for 40 to 50 minutes or until set and golden brown on top.

9. Finish & serve. Garnish with extra scallions and serve warm.

Expert Tips & Tricks

• Cut the bagels into uniform cubes so the egg mixture absorbs evenly.
• Add chunks of cream cheese for pockets of creamy texture.
• Add sautéed red onion or red bell pepper for more depth and color.
• Use cheddar cheese, swiss cheese, or gruyere cheese for a richer, more traditional casserole.
• If the top browns too quickly, tent with foil.

Storage & Reheating

• Refrigerate: Store leftovers in an airtight container for up to 4 days.
• Reheat: Warm slices in the microwave or in a 325°F oven until heated through.
• Freeze: Freeze individual portions for up to 2 months.

Did you have a chance to make this recipe? If so, please leave me a 5 star rating and review below. I always love and appreciate hearing from you!