Heat oven to 350º F. Grease bottom and sides of rectangular pan, 15 x10 x1 inch, with shortening. In medium bowl, mix flour, baking powder, cinnamon and salt; set aside. In large bowl, beat brown sugar, butter and vanilla with electric mixer on
medium speed until creamy. Beat in eggs and pumpkin until well mixed. Gradually beat in flour mixture. Spread in pan.