These are the most amazing snickerdoodle cookies! The pumpkin gives the cookies the most delicious flavor and texture!
In a mixing bowl whisk together your dry ingredients; flour, cornstarch, cream of tartar, baking soda, baking powder, salt, cinnamon, ginger, nutmeg, and allspice until blended.

In a stand mixer or with electric mixer, cream together butter, sugar, and brown sugar. Occasionally scrape down the sides and bottom of bowl until thoroughly mixed.
Mix in egg, then pumpkin puree and vanilla.

Slowly incorporate your dry ingredients to your mixing bowl just until combined.

Refrigerate dough for a couple of hours.
Preheat oven to 350 degrees.
In a small bowl, combine the remaining 1/4 cup sugar and 1 1/2 teaspoon ground cinnamon for rolling.
Scoop dough and roll into 1 inch balls. An ice cream scoop makes the perfect cookie dough ball. Roll dough ball into cinnamon and sugar mixture.

Transfer dough balls to a silpat or parchment paper lined baking sheet and space cookies about 2 inches apart.
Bake in a preheated oven for about 12 1/2 minutes. Cool on baking sheet for a few minutes prior to transferring to a cooling rack.
