Beat cream cheese and butter at medium speed with an electric mixer until creamy. Gradually add flour to butter mixture, beating at low speed until blended. Shape mixture into 48 balls, and place on a baking sheet; cover and chill 30 minutes.
Preheat oven to 350°. Place 1 dough ball into each cup of 2 lightly greased (24-cup) miniature muffin pans, and shape each into a pastry shell.
Whisk together eggs and next 4 ingredients. Pour into pastry shells.
Bake at 350° for 18 to 22 minutes or until filling is set. Cool in pans on wire racks 10 minutes. Remove from pans to wire racks; cool completely (about 20 minutes).
Chocolate Chess Tarts: Increase vanilla to 2 tsp. Microwave 2 (1-oz.) unsweetened chocolate baking squares, chopped, in a microwave-safe bowl at HIGH 1 to 1 1/2 minutes or until melted and smooth, stirring at 30-second intervals. Prepare recipe as directed, stirring chocolate into egg mixture in Step Garnish with shaved chocolate or chopped toasted pecans.
Lemon-Coconut Tarts: Prepare Buttermilk Chess Tarts as directed, omitting buttermilk and vanilla and stirring 1/3 cup fresh lemon juice and 1 tsp. coconut extract into egg mixture in Step Garnish with toasted coconut and lemon rind strips.