Warm up with this hearty Onion Soup Gratin recipe. Made with butter, onions, sugar and beef broth. Easy step-by-step instructions included.
This Onion Soup Gratin relies on simple, everyday ingredients such as butter, onions, sliced thinly, sugar and salt and pepper. It comes together quickly and makes 4 servings, at about 262 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