In a large skillet over medium heat, cook bacon and onion until the bacon is crisp and the onion is translucent. Remove from heat and set aside.
In a medium bowl, combine bread crumbs and melted butter. Mix until combined.
In a separate bowl, whisk together eggs, milk, salt, and pepper. Stir in bacon and onion.
Spray a 9x13 inch baking dish with cooking spray. Spread bread crumb mixture on the bottom of the dish. Pour egg and bacon mixture over the bread crumbs.
Bake for 30 minutes, or until the center is set.
Interesting Facts
This recipe is a great way to use up any leftover bacon.
This casserole can be served with a side of fruit or a salad for a complete meal.
This casserole can be made ahead of time and reheated for a quick and easy breakfast.