Rub the inside of the fondue pot or saucepan with the crushed garlic clove. Discard the garlic. Add the wine and bring to a simmer. Dissolve the cornstarch in the water and whisk into the wine. Bring to a boil and cook for 2 minutes. Reduce the heat to low and whisk in the cheese, a little at a time. Stir in the Kirsch and season with the nutmeg and pepper. Serve the fondue with the toasted cubes of bread.