Prep 25 mins
Cook 2 hrs 15 mins
Supposedly a recipe from the kitchens of Le Grappe d'Or, Lausanne, Switzerland.
Make and share this Soupe a L'oignon (French Onion Soup) recipe from Food.com.
- In a heavy bottomed frying pan, melt the butter and the sugar together.
- Add the onions and slowly brown them until they are dark brown (about 30 minutes). Stir frequently remembering to use a wooden spoon to occasionally lift off the brown from the bottom of the pan.
- Add flour, cooking and stirring it for 2-3 minutes.
- Add broth and simmer partially covered for 1 hour.
- To serve, ladle each serving into an oven proof serving bowl and top with one crouton per bowl. Cover each bowl generously with Swiss cheese and sprinkle with Parmesan cheese.
- Bake covered on a baking sheet at 325F for 15 minutes and then uncovered for another 10 minutes. Serve.