Heat the oven to 350 degrees F. Butter a 1-quart souffle dish or casserole. Heat the margarine in a 2-quart saucepan over low heat until melted. Stir in the flour, sugar, cumin, nutmeg, and red pepper. Cook over low heat, stirring constantly, until the mixture is smooth and bubbly. Stir in the milk, heat to boiling, stirring constantly. Boil and stir for 1 minute. Beat the egg yolks slightly in a medium bowl. Stir at least half of the hot mixture gradually into the egg yolks. Stir the hot mixture back into the saucepan. Boil and stir for 1 minute. Remove from the heat and stir in the onion, chilies, and corn. Beat the egg whites in another medium bowl on high speed, on an electric mixer, until stiff. Stir about 1/4 of the egg whites into the corn mixture. Fold the corn mixture into the remaining egg whites. Carefully pour the mixture into the souffle dish. Bake uncovered until a knife inserted in the center comes out clean, about 50 minutes. Prepare the Green Chile Cheese Sauce. Serve the souffle with the sauce when souffle is done.
GREEN CHILE CHEESE SAUCE: Heat all the ingredients over low heat, stirring constantly, until the cheese is melted.