Heat oven to 350°F. Spray 13x9-inch pan with cooking spray. In bowl, mix flour, powdered sugar and 1/2 teaspoon of the lemon peel. Cut in butter, using pastry blender (or pulling 2 table knives through mixture in opposite directions), until crumbly. Press in bottom of pan. Bake 20 to 22 minutes or until light brown. Meanwhile, in bowl, beat cream cheese and granulated sugar with electric mixer on medium speed until smooth. Beat in eggs, one at a time, until blended. Stir in lemon juice and remaining 1/4 teaspoon lemon peel, beating well. Spread preserves over shortbread. Pour cream cheese mixture over preserves, spreading to edges.