3 tbsp unsalted butter
1 tbsp olive oil
5 cups yellow onions
thinly sliced
1 tsp table salt
plus additional to taste
1/4 tbsp granulated sugar
helps the onions to brown
3 tbsp all-purpose flour
1/2 cup dry white wine
or dry white vermouth
2 qt beef stock
for vegetarian version sub with mushroom stock
freshly ground black pepper
3 tbsp cognac
or brandy
1 tbsp onion
2 cups Swiss Gruyere
grated, or a mixture of Swiss and Parmesan cheese
1 tbsp butter
16 rounds French bread
1-inch thick, toasted until hard
For the Soup
Melt the butter and oil together in the bottom of a 4- to 5-quart saucepan or Dutch oven over moderately low heat.
Add the onions, toss to coat them in oil, and cover the pot. Reduce the heat to real low and let them slowly steep for 15 minutes.
After 15 minutes, uncover the pot, raise the heat slightly and stir in the salt and sugar. Cook onions, stirring frequently, for 30 minutes until they have turned an even, deep golden brown.
After the onions are fully caramelized, sprinkle them with flour and cook, stirring, for 3 minutes.
Add the wine, then stock, a little at a time, stirring between additions. Season to taste with salt and pepper.
Bring to a simmer and simmer, partially covered, for 30 more minutes, skimming if needed. Correct seasonings if needed but go easy on the salt as the cheese will add a bit more saltiness.
Stir in the cognac.
Set aside until ready
To Serve
Bring the soup back to a boil and divide among the individual cups/bowls. To each vessel, add 1/2 teaspoon grated raw onion and a tablespoon of grated cheese. Stir to combine.
Dab your croutons with a tiny bit of butter and lay on top of sheet pan. Mound grated cheese on top. At this point you can bake in the oven or brûlée with a torch.
Place bread and cheese on top of soup and serve with a small demitasse spoon.
While this recipe is originally made with beef stock, it also tastes just as good with mushroom stock or vegetable stock.