1. Heat oven to 350 degrees F. Line 13 x 9 x 2-inch baking pan with aluminum foil. Coat with nonstick cooking spray.Crust:
2. In bowl, stir together butter, powdered sugar, vanilla and salt. Gradually stir in flour until smooth. Press dough over bottom of prepared pan.
3. Bake in 350 degree F oven 20 minutes or until edges brown.Filling:
4. In large bowl, mix granulated sugar and flour. Whisk in eggs until smooth. Stir in lemon rind and juice. Fold in berries. Pour filling over crust.
5. Bake in 350 degree F oven until set, 30 minutes. Let cool in pan on wire rack. Dust with the 1/4 cup powdered sugar. Cut into diamonds. Makes 20 diamonds.