One great tip is prepping the ingredients and assembling the casserole about one or two days before you bake it, ensuring it's ready to go when dinner time rolls around.
Prepping a casserole a day or two before cooking provides convenience and eliminates any last-minute rush. It also results in a casserole with a rich and deeper taste.
The extra time spent in the refrigerator allows separate ingredients to be fully incorporated, which is especially beneficial for casseroles containing meat.
The meaty juices will fuse with ingredients like starch, cheese, and vegetables over time, which can exponentially ramp up the flavor of the finished dish.