How To Make Preheat oven to 375° and grease a small 10oz ramekin or baking dish. Remove the sandwich from its packaging and cut it into 1” pieces and place the pieces into the prepared dish along with the cheese. In a small bowl, whisk together egg, milk, salt, and pepper until blended; pour over the cubed sandwich and cheese. Place the ramekin on a baking sheet and bake for 25-30 minutes. Let the casserole rest for 5 minutes before enjoying.