Freezer Meal Option: After topping with remaining beef and pasta mixture, cover the baking dish tightly with heavy duty foil, crimping the edges tightly. Transfer the unbaked casserole to the freezer. To serve, thaw the casserole in refrigerator overnight. Remove it from the refrigerator 30 minutes before baking. Top it with the final layer of cheeses and bake the casserole as directed, increasing the time as necessary to heat it through if it is still chilly when going in the oven.