In a small bowl toss together Swiss or Gruyere cheese and flour. In a medium saucepan heat buttermilk, wine, or apple cider over medium heat until small bubbles rise to the surface. Stir in cheese mixture, little by little, making sure cheese has melted before adding more. (Stir constantly and continue to add cheese until all is mixed in.) Stir until cheese mixture bubbles gently. Stir in nutmeg, mace, or caraway seed.
Pour cheese mixture into a small fondue pot. Keep cheese mixture warm over fondue burner. Sprinkle with walnuts or pecans. Serve with bread cubes and vegetable dippers. Makes 2 servings.