PREHEAT oven to 350°F. Sift flour with baking powder, salt, baking soda and spices; set aside. Mix molasses and water until well blended; set aside.
BEAT shortening in large bowl with electric mixer on medium speed until creamy. Gradually add sugar, beating until light and fluffy. Blend in egg. Add flour mixture alternately with the molasses mixture, beating well after each addition. Pour into greased 8-inch square baking pan.
BAKE 35 min. or until toothpick inserted in center comes out clean. Cut into 9 squares. Serve warm or at room temperature topped with the Lemon Sauce.