In a saucepan, melt together 3 cups shredded processed American or American cheese and 2 tablespoons butter over low heat. Stir in 1 teaspoon Worcestershire sauce, 1/4 teaspoon dry mustard, and dash cayenne pepper. Beat together 2 egg yolks and 1/2 cup beer. Add the yolk mixture to the saucepan. Cook and stir over medium heat until mixture thickens and begins to bubble around the edges. Makes 2 cups.