How to Make It
1. Combine first 4 ingredients; stir with a whisk to combine.
2. Place granulated sugar and butter in a large bowl; beat with a mixer at medium speed until well blended (about 2 minutes). Add pumpkin puree and vanilla; beat at medium speed until well blended (about 1 minute). Add egg; beat at medium speed 30 seconds or until well blended. Add flour mixture; beat at low speed just until combined. Divide dough in half (dough will be soft); flatten each dough half into a 5-inch circle. Wrap each dough half in plastic wrap. Refrigerate 2 hours or until dough is firm (you can make and chill the dough up to a day ahead, too).
3. Preheat oven to 350°F.
4. Unwrap 1 dough portion. Roll between 2 sheets of lightly floured plastic wrap to a 1/4-inch thickness. Cut with cookie cutters into desired shapes. Reroll scraps, chilling briefly before cutting into shapes. Repeat procedure with other dough portion. Arrange cookies on baking sheets lined with parchment paper. Bake in batches at 350°F for 10 to 12 minutes or until just lightly browned around edges. Cool on pan 2 minutes; place cookies on a wire rack, and cool completely.
5. Combine powdered sugar and 1/4 teaspoon salt. Add milk, stirring until smooth. (If glaze is too thick, add a little more milk; if too thin, add a little more sugar.) Drizzle or spread glaze onto cookies to decorate. For sesame-coated bats or spiders, spread a thin layer of glaze onto cookies, and press down into sesame seeds to coat.