1. Add the butter to a light-colored saucepan over medium heat and cook, stirring often, until golden brown bits form and the butter smells nutty.

2. Pour the browned butter into a mixing bowl and let it cool for 10 to 15 minutes.

3. Blot the pumpkin puree with paper towels to remove excess moisture.

4. Stir the brown sugar and granulated sugar into the cooled brown butter until smooth.

5. Mix in the blotted pumpkin puree, egg yolk, and vanilla extract.

6. In a separate bowl, whisk together the flour, cream of tartar, baking soda, pumpkin pie spice, and salt.

7. Fold the dry ingredients into the wet ingredients until a soft dough forms.

8. Chill the dough for 25 to 30 minutes if it feels too sticky to scoop.

9. Mix the rolling sugar and cinnamon in a small bowl.

10. Scoop the dough into balls and roll each one in the cinnamon sugar mixture.

11. Place the dough balls on a parchment-lined baking sheet, leaving space between them.

12. Bake at 350°F for 10 to 12 minutes, until the edges are set and the centers still look soft.

13. Let the cookies cool on the baking sheet for 5 minutes, then move them to a wire rack.