Original French Onion Soup

The title may be a bit of an oxymoron, but it refers to the fact that I completely winged this dish.  It turned out to be a thoroughly plausible rendition.  I used the beef fat and braising vegetables from the beef ribs I made the other night.

3 large yellow onions
4 tablespoons unsalted butter
1 tablespoon beef fat
Vegetables from braised beef ribs
1 quart beef stock
8 ounces pumpkin ale
Red wine vinegar
Salt

Peel and cut the onions in to strips.  Melt the beef fat and butter in a pot large enough to hold at least a quart.  Saute the onions over medium heat until they are thoroughly caramelized.  They will turn brown but be careful not to let the butter burn.  Add the stock and beer and bring to a boil.  Wrap the vegetables in cheesecloth and tie up with kitchen string.  Add to the pot.  Reduce heat and simmer the soup for at 40 minutes.  Season with salt and vinegar to taste.  To serve, ladle into bowls and cover with crisped baguette slices and grated gruyere cheese.