In a stand mixer bowl, combine softened butter, packed brown sugar, 1 Tbsp pumpkin spice, and ¼ tsp cinnamon.
Mix on high speed until smooth and fluffy.
Add egg, yolk, and alcohol-free vanilla extract. Mix on low while scraping bowl to fully incorporate.
In a separate bowl, whisk 2¾ cups flour, 1 tsp baking soda, 1½ tbsp cream of tartar, and 1 tsp salt until well-combined.
Gradually add the dry ingredient mixture to the wet ingredients in 3-4 parts, mixing on low and scraping bowl as needed.
In a small bowl, combine granulated sugar and 1 tsp remaining pumpkin spice for coating.
Cover dough and refrigerate for 30 minutes while preparing the spice sugar.
Preheat oven to 350°F (175°C) and line baking sheets with parchment paper.
Roll 35g dough balls using a 35g kitchen scale.
Coat dough balls in spice sugar before placing on prepared baking sheets.
Bake for 8–10 minutes, rotating halfway through for even browning.
Let cookies cool on the baking trays completely before transferring to a wire rack.