Soupe a L'Oignon (French Onion Soup)

4 Tbs butter
2 Tbs vegetable oil
2 lbs (900 g) onions, thinly sliced (about 7 cups)
1 tsp salt
3 Tbs flour
2 quarts (2 L) beef, chicken, or vegetable stock (fresh or canned)
Salt and freshly ground black pepper to taste

For the croutes:
12 to 16 one-inch (2.5 cm) slices French bread
2 tsp olive oil
1 garlic clove, peeled and cut in half
1 cup grated Gruyere or Swiss cheese (Parmesan may be substituted)

Melt the butter with the oil in a large saucepan. Add the onions and the salt, stirring occasionally over low heat for 20 to 30 minutes, until the onions are golden brown. Sprinkle the flour over the onions and cook an additional 5 minutes, stirring occasionally. Add the stock and bring to a simmer, stirring frequently. Cook an additional 30 minutes, partially covered over very low heat. Taste the soup and adjust the seasoning. Meanwhile make the croutes by placing the slices of bread on a baking sheet in a single layer and bake at 325F (160C) for 15 minutes. Lightly brush both sides of each slice with the olive oil, turn over, and bake an additional 15 minutes, until crisp and golden brown. Rub each slice with the garlic clove. To serve place float the croutes on the soup in a tureen or individual soup bowls. Serve the cheese on the side, to be added by the diners. Serves 6 to 8.