1. Heat oven to 350°F. Line 12-inch metal pizza pan with foil.
2. Beat butter, granulated sugar, brown sugar and vanilla in medium bowl until fluffy; add egg, beating well. Stir together flour and baking soda; stir into mixture with chocolate chips. Spread batter evenly in prepared pan, spreading to 1-inch from edge.
3. Bake 20 to 25 minutes or until lightly brown and set. Cool completely; carefully lift cookie from pan and remove foil. Decorate as desired; cut into wedges to serve. Makea 8 to 10 servings.
VARIATION: "PERFECTLY CHOCOLATE" GIANT CHOCOLATE CHIP COOKIE: Stir in 1/3 cup HERSHEY'S Cocoa or HERSHEY'S SPECIAL DARK Cocoa with flour mixture.