In a 12-inch casserole or saucepan, heat the oil and butter. When the oil and butter are hot, add the garlic and onions, and stir fry for a minute. Cover and simmer over low heat for 15 minutes, stirring to make sure the onions Don't burn.
Add the wine and vinegar and cook for a minute to evaporate some of the alcohol. Add the flour and stir for a minute. Add the beef and chicken broth, thyme and bay leaf, and over medium heat, bring to a boil. Whisk, cover and simmer, over low heat for 30 minutes.
Preheat the oven to 350° F.
Cut the French bread on the diagonal into 16 (3/4-inch) thick slices. Toast them in the oven for 20 minutes, turning them once, or until dried out. When dried out, rub each side of the bread slices with garlic.
Discard the bay leaf. Season soup with salt and pepper. Stir in the cream if used and remove the soup from the heat.
Scatter some grated cheese on one side of the toasted bread and broil until cheese is golden. Garnish each portion with two cheese-covered bread rounds.
Makes: 8