Onion Soup with Beer and Cheddar

Ingredients

 * 4 tbsp unsalted butter
 * 4 med onions, peeled and sliced
 * 4 cup veal stock or low-sodium beef broth
 * ⅛ tsp freshly grated nutmeg
 * 12 oz dark beer
 * ½ lbs sharp cheddar cheese shredded
 * ½ tsp salt
 * freshly ground pepper to taste

Directions

 * 1) In a 3-quart heavy pot, preferably cast iron or copper, melt the butter over low heat.
 * 2) Add the onions and cook, covered, for 15 minutes.
 * 3) Uncover and continue to cook until the onions turn a deep golden color, about 30 to 40 minutes, depending on your pot.
 * 4) Stir frequently.
 * 5) Add the broth and the nutmeg, cover and bring to a boil.
 * 6) Reduce heat and simmer for 15 minutes.
 * 7) Meanwhile, in a small pot, bring the beer to a boil over medium heat and boil until the liquid has reduced by half.
 * 8) Remove from the heat and add the cheddar cheese, stirring until melted.
 * 9) Transfer this mixture to a blender.
 * 10) Add 1 cup of the onion soup and blend until smooth. Reserve.
 * 11) Remove the onion mixture from the heat and strain. Reserve the liquid.
 * 12) Transfer the onions to a blender or food processor and puree until very smooth.
 * 13) Return the purée to the pot, add the reserved liquid and the cheddar cheese mixture.
 * 14) Taste for salt and pepper.
 * 15) Serve piping hot in a tureen.