Corned Beef and Cabbage Casserole is a hearty and comforting dish that combines the flavors of traditional corned beef and cabbage with creamy mashed potatoes. This casserole is made by layering sliced corned beef, cooked cabbage, and mashed potatoes in a baking dish, then baking until golden and bubbly. It is a delicious way to enjoy the flavors of St. Patrick's Day all year round.