Try this homemade Heavenly Onion Casserole recipe the whole family will love. Made with butter, onions, mushrooms and swiss cheese. Easy step-by-step in…
This Heavenly Onion Casserole relies on simple, everyday ingredients such as butter, large onions, sliced thin, fresh mushrooms, sliced and shredded swiss cheese. It comes together quickly and makes 4 servings, at about 482 kcal each. The step-by-step instructions below are written to be easy to follow, even on a busy day.
It works as a light main on its own or as a starter alongside crusty bread, and it's just as good for a cozy night in as it is for feeding a crowd. Leftovers keep well, so it's a smart choice for meal prep too.
Updated Jun 30, 2026