Line an ungreased 9" tart pan with pie crust; press crust into fluted sides of pan and trim edges.
Bake at 450 degrees for 5 to 7 minutes; remove from oven. Sprinkle with 1/2 cup mozzarella cheese; let cool on a wire rack. Combine remaining ingredients; mix well and fill crust.
Reduce heat to 375 degrees; bake for about 20 minutes, or until bubbly on top.