Rum-Chocolate Fondue

7 ounces plain chocolate or Toblerone
1 1/2 tablespoons white rum (optional)
2 tablespoons butter
2 tablespoons Greek yogurt
1/4 pint whipping cream
Fruit pieces and/or marshmallows

Melt rum, chocolate and butter together in a pan over low heat. Remove from heat, and stir in yogurt and cream.

Serve with fruit pieces and/or marshmallows.

Serves 4.