Sift together flour, baking powder, salt and cinnamon; set aside. Cream together shortening and sugar in mixing bowl until light and fluffy, using electric mixer at medium speed. Beat in egg. Combine pumpkin and milk in small bowl. Add dry ingredients alternately with pumpkin mixture to creamed mixture, stirring well after each addition. Spoon batter into paper-lined 2 1/2-inch muffin-pan cups, filling 2/3rds full. Bake in 350 degree F. oven 20 minutes or until golden brown. Serve hot with butter and homemade jam.