Warm up with this hearty Caramelized Onion Soup Au Gratin (Low Carb, But You Won'T Notice recipe. Made with onion, shallot, butter and sugar substitute.…
This Caramelized Onion Soup Au Gratin (Low Carb, But You Won'T Notice relies on simple, everyday ingredients such as chopped onion, shallot, minced, butter and beef broth. It comes together quickly and makes 4 servings, at about 245 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