In a large mixing bowl, add in the butter and sugars.
½ cup unsalted butter, ½ cup granulated sugar, ¼ cup light brown sugar
Using a stand or hand mixer, beat until creamy and smooth.
Add in the egg yolk, vanilla, and pumpkin puree.
1 egg yolk, 1 teaspoon vanilla extract, ¼ cup pumpkin puree
Mix until fully combined.
Once mixed, add in the flour, pumpkin pie spice, ground cinnamon, baking soda, cream of tartar and salt.
1½ cups all-purpose flour, 1 teaspoon pumpkin pie spice, ½ teaspoon ground cinnamon, ½ teaspoon baking soda, 1 teaspoon cream of tartar, ¼ teaspoon salt
Mix until a sticky dough forms.
Cover and place in the refrigerator for 20 minutes.
Once chilled, preheat the oven to 350 degrees Fahrenheit.
Mix the granulated sugar and cinnamon until well combined.
2 Tbsp. granulated sugar, 1 tsp. ground cinnamon
Using about 2 Tbsp. of the dough, form into a ball using the palms of your hands.
Place each dough ball into the cinnamon sugar, being sure it is fully coated.
Once coated, place on a baking sheet lined with parchment paper, leaving 1½ in. of space in between each cookie.
Bake for 10-13 minutes or until the cookies are set around the edges and soft in the center.
Remove and allow to cool to a desirable temperature.