Created by KarenSTL on February 8, 2018
Step 1: Spray 8x8 square baking dish with cooking spray.
Step 2: Place bread in dish and sprinkle with cheese.
Step 3: Mix eggs, milk, mustard, salt, onion and pepper in a mixing bowl. Pour over bread.
Step 4: Sprinkle sausage on top of the casserole. Cover and chill for 12-24 hours (do not skip this step!).
Step 5: Preheat oven to 325 degrees. Bake uncovered for approximately 1 hour. Tent with foil if top begins to brown too quickly.