NOTE: If you would like to make this ahead of time prepare all the way through the cheese step. At this point you can cover and leave in regrigerator for up to 2 days before finishing. Or you could also freeze for up to 3 months. When ready to cook whisk egg mixture together, poor over casserole, cover and bake as advised above. You will need to add 15+ minutes of cooking time if you are placing frozen casserole in oven.