Preheat oven 300 F. In med bowl combine flour, soda, salt, and pumpkin pie spice. Mix well with wire whisk. Set aside. In lg bowl blend sugars with mixer set at med speed. Add butter and beat to form a grainy paste. Scrape sides of bowl, then add egg, pumpkin, and vanilla. Beat at med speed until light and fluffy. Add flour mixture, raisins, and walnuts. Blend at low speed just until combined. Do not overmix. Drop by rounded Ts onto ungreased cookie sheets, 1 1/2" apart. Bake 22-24 mins until cookies are slightly browned along edges. Immediately transfer cookies to a cool surface.