Heat oven to 425 degrees F. Carefully unroll bread dough; press into bottom of a greased 15x10x1-inch baking pan. Sprinkle evenly with about half of the cheese, all of the mushrooms, green onion, pistachios, and fennel seed. Top with remaining cheese.
Bake about 15 minutes or until edges of crust are golden brown. Cut into 15 squares; cut each square in half diagonally. Makes 30 servings.