Beat the butter and the sugars until light and fluffy.
Mix in the egg, vanilla, salt, and baking soda.
Add the pumpkin and mix until incorporated. The batter may look curdled but that's normal.
Stir in the spices and flour and completely incorporate.
Finish by stirring in the pecans.
Divide the dough into two sections and make logs on parchment paper. Roll up and place in the freezer or refrigerator until well chilled and firm. If you want to keep in the freezer, make sure logs are in an airtight container. Once chilled, preheat oven to 350°F.
Slice ¼-inch cookies and place on an ungreased cookie sheet.
Bake 10-12 minutes until puffed and firm to the touch.
Remove from oven and cool on the baking pan for five minutes then on cooling racks until room temperature. If you want to add a glaze, glaze once the cookies are room temperature.
For the glaze
Mix ingredients until a smooth glaze with no lumps is achieved. Adjust milk and sugar to achieve a smooth and fluid glaze.
Dip the top of the cookie in the glaze then finish with sprinkles, if desired. The glaze will harden and the cookies will be devoured!