Date Nut Cake

Preheat oven to 350° F. Grease and flour 9-inch square baking pan and set aside.Combine Date filling and water in small bowl and stir until blended. Set aside.Beat butter and sugar in medium-size bowl with electric mixer until light and fluffy. Add vanilla and egg and beat until blended. Stir flour, baking soda and salt until mixed and add to butter mixture alternately with date mixture, beginning and ending with dry ingredients. Beat until smooth. Stir in chopped walnuts. Spread batter evenly in prepared pan.Bake 50 to 60 minutes or until cake tester inserted in center comes out clean. Cool completely in pan on wire rack. Cut into nine 3-inch squares and serve with whipped cream, if desired.