Easy Overnight Everything Bagel Breakfast Casserole

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