Unfold piecrust according to package directions. Place in a 9-inch quiche or pie dish. Prebake according to package directions. Remove from oven. Sprinkle with 1/2 cup Mozzarella cheese. Adjust oven to 375°F.
Cut tomatoes into wedges, drain on paper towels. Arrange wedges on top of melted cheese in the baked pie shell.
In a food processor bowl, combine basil and garlic; process until coarsely chopped. Sprinkle over tomatoes.
In a medium mixing bowl, combine remaining Mozzarella cheese, mayonnaise, Parmesan cheese and pepper. Spoon cheese over top, spreading evenly to cover basil mixture.
Bake at 375°F for 35-40 minutes, or until top is golden and bubbly. Serve warm. Sprinkle with basil leaves if desired.