You can make fondue even if you don’t own a multi-piece set. Any enamel or ceramic-lined pot will do. Instead of the classic Swiss cheeses like Gruyère or Emmental (or Appenzeller, Fribourg, or Vacherin), any good melting cheese—like cheddar, Jack, Comté, or fontina—will work fine. Even the alcohol is flexible: Dry and acidic white wi…