Preheat the oven to 350 degrees.
Grease a 9x13 baking dish.
Cut each everything bagel into 1 inch sized cubes.
Pour the bagel cubes into the baking dish.
In a medium bowl, mix together the eggs, milk, everything bagel seasoning, salt, and pepper.
Pour this egg mixture over the chopped bagels.
Sprinkle 1 cup of cheddar cheese over the bagels and egg mixture.
Toss this all together in the baking dish until the bagels are evenly coated.
Sprinkle the remaining 1 cup of cheese on top of the casserole.
Bake for 30-35 minutes.
Sprinkle on chopped chives and more everything bagel seasoning if desired.