Everything Bagel Breakfast Casserole

This crowd-pleasing Everything Bagel Breakfast Casserole is about to make your special-occasion breakfast or brunch a whole lot more delicious! It is best when assembled the night before allowing the bagels to soak up the egg custard. Just mix it all up and put it in the fridge overnight, then bake away in the morning.

I love a good hearty breakfast, particularly on a holiday weekend when you have time to linger at the table and enjoy a bit of a feast with family and friends. For serving a crowd, a great breakfast casserole can’t be beat. If you’ve been searching for one that is foolproof and crowd-pleasing, this one made with tasty everything bagels will end your search.

Tucked within custard-soaked everything bagels are bites of browned sausage, caramelized onions, flecks of sautéed spinach, bell pepper, and of course loads of grated cheese. Once baked, the deep-dish breakfast casserole emerges puffed and golden-topped with perfectly set eggs that are loaded with flavour.

Best of all, you can, and should prepare it entirely the night before then slide it into a hot oven an hour before you plan to serve it. A perfect no-stress centerpiece for a special-occasion breakfast or brunch when you need to feed en masse. Simple and delectable.

Ingredients And Notes

This recipe is adapted from Chrissy Teigen’s cookbook Cravings: Hungry for More. Her everything bagel breakfast casserole has become a huge hit in our household. I use a little less cheese, fresh spinach, and the addition of red peppers and green onions. The ingredient list may seem a bit long but the beauty of any breakfast casserole is that they are endlessly adaptable and can be a true ally to the fridge clean-out. Keep the base the same, then use any cheese, protein, or veggie you’d like.

• Everything Bagels: You will need 3 or 4 everything bagels for this recipe. Use 4 if your bagels are small. If you have large bagels, 3 should be plenty. If you can’t find everything bagels, you can use plain bagels and top with everything bagel seasoning which is sold at most well-stocked grocery stores.
• Breakfast sausage: Sausage adds a lot of flavour and makes the casserole a little heartier but you can absolutely omit it if you prefer. You could also use bacon, ham, pancetta, or a plant-based sausage.
• Onions: I like my breakfast casseroles to be extra savoury so onions to me are a must.
• Eggs: You will need 8 eggs for this everything bagel breakfast casserole.
• Milk: You can use half and half, whole milk, or plant-based milk. The more fat the milk has, the better texture.
• Dijon mustard: The sharp flavour of dijon helps prevent the casserole from being too eggy.
• Cheese: I love the flavour and texture of Gruyere for casseroles but feel free to use your favourite cheese here. Cheddar, mozzarella, Fontina, Asiago, etc., they all work.
• Baby spinach: No amount of greens are going to make this casserole “healthy” but I always like to throw some in for good measure. I haven’t tried using frozen spinach for this casserole, but I imagine it would work well if you want to go that route. That said, it is so easy to just sauté the fresh spinach in the same skillet you use to cook the onions and sausage.
• Red pepper and scallions: For colour and a bit more savoury flavour I like to add some extra veggies. Feel free to omit, or add other veggies if you prefer.
• Salt and pepper: To season
• Cream Cheese: Bits of cream cheese top the casserole for a classic bagel and cream cheese combo. So good!
• Everything Bagel Seasoning: Optional, but if you have some on hand, it doesn’t hurt to sprinkle the casserole with some additional seasoning for extra flavour.

How To Make Everything Bagel Breakfast Casserole

1. Grease a 9×13-inch baking dish, or equivalent.
2. Heat a large skillet over medium heat. Add the sausage and cook until golden-brown and cooked through, about 8 to 10 minutes. Transfer to a paper towel-lined plate and don’t wipe the skillet.
3. Add the onion to the skillet and cook until slightly softened and caramelized, about 5 minutes. Transfer to a large bowl. In the same skillet, sauté the spinach until wilted, about 2 minutes then transfer to the bowl with the onions. Cut the sausage into 1-inch pieces and add to the bowl with the onion and spinach along with the bagel chunks, half of the gruyere cheese, red peppers, scallions, salt and pepper. Using your hands or a spatula, toss everything together until well combined. Transfer the bagel mixture to prepared baking dish and arrange everything in a single layer.
4. In a separate mixing bowl, whisk together: eggs, milk, dijon mustard, salt, and pepper. Pour the egg mixture evenly over top. Dot with the pieces of cream cheese.
5. Cover tightly and refrigerate for 2 to 6 hours, but preferably overnight.
6. When ready to bake, sprinkle with remaining gruyere cheese and cover with foil. Bake for 40 minutes a preheated 350ºF oven. Remove foil and bake until top is golden brown and egg mixture is set, about 15 to 20 minutes longer. Let sit for 5 to 10 minutes before serving.

Frequently Asked Questions

Make it Vegetarian

To be honest, I love to keep this everything bagel breakfast casserole vegetarian and serve some turkey bacon or breakfast sausages on the side. When omitting the sausage, feel free to add more spinach, bell peppers, or other veggies.

Make Ahead and Storage

• Make Ahead: Assemble casserole completely, but don’t top with remaining cheese. Cover tightly and store in the refrigerator overnight. When ready to bake, top with remaining cheese and bake as instructed.
• Store: Everything bagel breakfast casserole leftovers are delicious for days. Store any leftovers in an airtight container in the refrigerator for up to 3 days. Reheat in a preheated oven until warmed through.
• Freeze: Assemble and bake the casserole. Cool completely and cover tightly with two layers of foil. When ready to use, thaw in the refrigerator overnight then place in a 350ºF preheated oven and bake, covered, until warmed through.

More Breakfast/Brunch Recipes To Try

• Baked French Toast
• Fluffy Yogurt Pancakes
• Dutch Baby with Caramelized Apples

Print Recipe Pin Recipe

Everything Bagel Breakfast Casserole

Author: Sandra Valvassori

This crowd-pleasing Everything Bagel Breakfast Casserole is about to make your special-occasion breakfast or brunch a whole lot more delicious! It is best when assembled the night before allowing the bagels to soak up the egg custard. Just mix it all up and put it in the fridge overnight, then bake away in the morning. 

Prep Time 20 minutes mins

Cook Time 55 minutes mins

Total Time 1 hour hr 15 minutes mins

Servings 8 – 10

Ingredients  

1x2x3x

• 1 pound uncooked breakfast sausage (omit to make vegetarian)
• 1 tablespoon butter plus extra for greasing pan
• 1 large onion thinly sliced
• 5 ounces baby spinach
• 3 large day-old everything bagels (or 4 small) cut into 2-inch chunks
• 1 small red bell pepper finely chopped
• 3 scallions finely sliced
• 1 1/2 cups grated Gruyère, or sharp cheddar, or a mix divided
• 2 teaspoons kosher salt and freshly ground black pepper divided
• 8 large eggs
• 2 cups whole milk, or half and half, or a mix
• 2 tablespoons Dijon mustard
• 4 ounces cold cream cheese cut into small cubes

Instructions 

• Grease a 9×13-inch baking dish, or equivalent.
• Heat a large skillet over medium heat. Add the sausage and cook until golden-brown and cooked through, about 8 to 10 minutes. Transfer to a paper towel-lined plate and don’t wipe the skillet.
• Add the butter to the skillet and once melted add the onion. Cook until slightly softened and caramelized, about 5 minutes. Add the spinach and sauté until wilted, about 2 minutes. Transfer onion-spinach mixture to a large bowl. Cut the sausage into 1-inch pieces and add to the bowl along with the bagel chunks, half of the gruyere cheese, red peppers, scallions, salt and pepper. Using your hands or a spatula, toss everything together until well combined. Transfer the bagel mixture to prepared baking dish and arrange everything in a single layer.
• In a separate mixing bowl, whisk together: eggs, milk, dijon mustard, salt, and pepper. Pour the egg mixture evenly over top. Dot with the pieces of cream cheese. Cover tightly and refrigerate for 2 to 6 hours, but preferably overnight.
• Preheat oven to 350ºF and let the chilled casserole sit at room temperature while the oven preheats.
• Sprinkle with remaining gruyere cheese and cover with foil. Bake for 40 minutes. Remove foil and bake until top is golden brown and egg mixture is set, about 15 to 20 minutes longer. Let sit for 5 to 10 minutes before serving.

Notes

Recipe adapted from Chrissy Tiegan’s Cravings: Hungry For More 

Make Ahead and Storage

• Make Ahead: Assemble casserole completely, but don’t top with remaining cheese. Cover tightly and store in the refrigerator overnight. When ready to bake, top with remaining cheese and bake as instructed.
• Store: Everything bagel breakfast casserole leftovers are delicious for days. Store any leftovers in an airtight container in the refrigerator for up to 3 days. Reheat in a preheated oven until warmed through.
• Freeze: Assemble and bake the casserole. Cool completely and cover tightly with two layers of foil. When ready to use, thaw in the refrigerator overnight then place in a 350ºF preheated oven and bake, covered, until warmed through.

Keywords: Breakfast, Casserole, Evreything bagel

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