Place the cheeses in a large bowl and sprinkle with the cornstarch, tossing to evenly coat the cheese. All cheese fondue recipes should contain some sort of starch, preferably flour or cornstarch; they protect the cheese from separating and curdling when melted.
Rub the inside of a fondue pot with the cut side of the sliced garlic and then discard. Place the pot over a sterno flame. Add the wine and bring to a gentle simmer, until tiny bubbles begin to rise to the surface, the wine's natural acidity makes the cheese smooth and creamy. Gradually stir the cheese into the simmering wine, allowing each handful to melt before adding another; melting the cheese slowly encourages a smooth fondue. Once the consistency is smooth, stir in the mustard, nutmeg and pepper.
Plating: Arrange an assortment of bite-size dipping foods, such as chunks of baguette, vegetables, and meats, on a lazy Susan around the fondue pot. Spear with fondue forks or wooden skewers, dip, swirl, and enjoy! If the fondue begins to get too thick during the meal, add some more wine and stir vigorously until the fondue is smooth. Be careful not to let the fondue boil.
Cheese fondue can be made hours before serving. Just keep it warm and stir frequently.