Grate the cheeses. In a medium bowl, toss the cheese with the cornstarch. Set aside.
Rub the inside of the fondue pot with the garlic clove. Set that aside as well.
In a medium to large saucepan over medium heat, bring the wine and lemon juice just to a simmer. Gradually stir in the cheese adding a small amount at a time and stirring until melted before adding more. Stir in the mustard, salt, and nutmeg.
Pour the mixture into the prepared fondue pot and set over a low flame. Serve with bite-size pieces of your preferred dippers.
