French Onion Soup
["6 Tbsp. butter", "6 large Spanish yellow onions, sliced", "2 qt. beef stock or 6 (10 1/2 oz.) cans beef broth", "salt and pepper to taste", "butter", "6 slices French bread (1/2-inch thick)", "1/2 lb. Swiss cheese, grated", "6 egg yolks, lightly beaten", "6 oz. Port wine"]
["Melt butter in large saucepan.", "Cook onions over lowest heat until limp but not brown.", "Add beef stock, salt and pepper. Simmer 15 minutes over medium heat.", "Puree hot soup in batches in a blender or processor.", "Heat butter or oil in skillet; brown bread on both sides.", "Combine egg yolks and Port wine in bowl; reserve.", "Place 1 slice of bread in each of 6 bowls; pour soup and sprinkle cheese over.", "Place under preheated broiler for 1 minute or until cheese is melted and slightly brown.", "Cut crust of cheese with a tablespoon and pour in 1/4 cup of egg mixture.", "Serves 6 to 8."]
["butter", "Spanish yellow onions", "beef stock", "salt", "butter", "bread", "Swiss cheese", "egg yolks", "wine"]