In a large skillet, melt the butter over medium heat, stirring frequently until golden brown and nutty fragrant. Then cool to 70-75°F.

Press pumpkin puree with paper towels to remove excess moisture and set aside.

Combine cooled butter, granulated sugar, and dark brown sugar, mixing until resembling wet sand. Add egg yolks, vanilla extract, and pumpkin puree, blending until smooth.

Whisk together flour, pumpkin spice, baking soda, cream of tartar, and sea salt in a separate bowl and fold into the wet mixture until just combined.

Cover the bowl with plastic wrap and refrigerate the dough for at least 5 minutes.

Mix the granulated sugar and cinnamon for the coating in a small bowl.

Preheat your oven to 350°F (175°C). Scoop about 3 tablespoons of dough, roll into balls, and coat in cinnamon sugar before placing on lined baking trays.

Bake for 10-12 minutes until edges are golden brown and centers are slightly puffed. Remove before fully set for chewiness.

Cool on the trays for 5 minutes before transferring to a wire rack to cool completely.