Heat oven to 425F. Cook and stir 2/3 cup sliced fresh mushrooms in 1/4 cup butter or margarine until mushrooms are tender; drain. Prepare pastry for Two-crust Pie as directed on 1 pkg. Betty Crocker pie crust mix except - roll dough 1/8" thick and cut into 2 1/2" rounds.

On each round, place on 1 1/4" square sliced Swiss cheese and 1 mushroom slice; repeat. Top with another cheese square and a pastry round. Moisten edges with water; press with fork to seal. Prick tops. Bake on ungreased baking sheet about 12 minutes. Spear rounds and swirl in Cheese Fondue or your favorite sauce.

18 appetizers.