In a medium mixing bowl, sift together flour, baking soda, baking powder and salt. In a large bowl, using a mixer on medium speed, beat together butter, sugar, brown sugar and vanilla until creamy. Beat in egg and pumpkin until combined. Reduce mixer speed to low and beat in flour mixture until just combined. Stir in chocolate chips until combined. Chill batter in freezer for 20 minutes.
Heat oven to 350 degrees F.
Drop rounded spoonfuls of dough onto cookie sheets, spacing about an inch apart. Bake 9 minutes. Press candy corn and M&M's into each cookie. Return pan to oven and bake an additional 4-5 minutes, or until crisp around edges. Cool for 10 minutes on cookie sheet before transferring to wire racks.