Introduction

This Everything Bagel Casserole is a savory, satisfying breakfast or brunch dish packed with layers of flavor. Featuring chopped everything bagels, crispy bacon, spinach, and creamy cheeses, it’s a delightful twist on traditional egg casseroles. Perfect for feeding a crowd or meal prepping for busy mornings.

A close-up of a baked dish in a white oval ceramic dish filled with layered toasted bread pieces that are golden brown with some darker grilled spots, scattered bright red cherry tomato halves, and wilted dark green spinach leaves. On top, there are uneven dollops of melted white cheese that is slightly browned. Small chopped green onions are sprinkled across the surface along with black and white sesame seeds and some black seasoning flakes. The dish sits on a white marbled texture background. photo taken with an iphone --ar 4:5 --v 7

Ingredients

3 day-old everything bagels, chopped into bite-sized pieces*
6 slices cooked bacon, chopped
2 tablespoons butter
1/2 large or 1 small onion, thinly sliced (about 2 cups)
6 ounces or 4 cups baby spinach (fresh or frozen)
Salt and pepper, to taste
2 cups cherry tomatoes, halved OR 15-ounce can diced tomatoes, drained
1 tablespoon Everything But The Bagel (EBTB) Seasoning*
1 1/2 cups grated Gruyere cheese
1 1/2 cups grated sharp cheddar
8 large eggs
2 cups milk
1 tablespoon dijon mustard
6 ounces cream cheese, cut into bite-sized pieces
Optional: sliced scallions, for garnish

Instructions

Step 1: Preheat oven to 375 degrees F. Grease a 9×13 baking dish thoroughly.
Step 2: In a large skillet, melt the butter over medium heat. Add the sliced onion and sauté until translucent, about 6–8 minutes. Then add the spinach and cook until wilted. Season the mixture with salt and pepper to taste.
Step 3: In a large bowl, combine the chopped bagel pieces, sautéed onion and spinach mixture, cooked bacon, your choice of tomatoes, both cheeses, and Everything But The Bagel seasoning. Mix gently to combine.
Step 4: In another bowl, whisk together the eggs, milk, and dijon mustard until smooth and combined. Season with salt and pepper as desired.
Step 5: Transfer the bagel mixture into the prepared baking dish and spread evenly. Pour the egg mixture over the top. Dot the surface with bite-sized pieces of cream cheese, distributing them evenly.
Step 6: Bake uncovered at 375 degrees F for 45 to 55 minutes, until the edges are golden brown and the center is set (or reaches 160 degrees F).
Step 7: Allow the casserole to cool for about 10 minutes before serving. Garnish with sliced scallions if desired for a fresh finish.

Tips & Variations

Use day-old bagels for better texture; fresh bagels may become too soggy.
Swap baby spinach for kale or swiss chard for a different leafy green flavor and texture.
Try substituting bacon with cooked sausage or ham to vary the protein.
If you like it spicier, add a pinch of red pepper flakes to the egg mixture.
For a dairy-free option, use plant-based milk and omit cheeses or use vegan cheese alternatives.

Storage

Store leftovers in an airtight container in the refrigerator for up to 3 days. Reheat individual portions in the microwave until warmed through. This casserole also freezes well—wrap tightly and freeze for up to 2 months. Thaw overnight in the fridge before reheating.

How to Serve

A clear bowl holds four distinct layers of ingredients arranged side by side. Starting from the top right, there are bright red halved cherry tomatoes with a juicy, shiny texture. To their left, a layer of chopped, toasted bread pieces is golden brown with specks of black and white seasoning on top. Below the bread, dark brown crispy bacon pieces form a rough textured cluster. To the right of the bacon, sautéed spinach mixed with light brown cooked onion strips creates a soft, leafy green layer. The bowl is placed on a white marbled surface. photo taken with an iphone --ar 4:5 --v 7

Serve this delicious recipe with your favorite sides.

FAQs

Can I make this casserole ahead of time?

Yes, you can assemble the casserole the night before and refrigerate it. Bake it fresh the next morning for best texture and flavor.

Can I use bagel seasoning other than Everything But The Bagel?

Absolutely! Feel free to experiment with your favorite seasoning blends, but Everything But The Bagel adds a distinctive savory crunch that complements this recipe perfectly.