Grease a 15x10x1" baking pan. Stir together flour, baking soda, spices, and salt. In a 2-quart saucepan combine raisins, shortening or oil, and water. Bring to a boil. Remove from heat. Cool for 10 minutes. Stir in sugar, honey, and egg. Add dry ingredients, stirring until smooth. Stir in walnuts. Turn into pan and bake at 350 for 18 to 20 minutes. Cool on a wire rack. Sprinkle powdered sugar over top. Cut into bars.