Preheat your oven to 350°F (180°C) and line two baking trays with parchment paper.

Brown the butter in a saucepan over medium heat until golden and nutty, then cool for 45-60 minutes.

Prepare the pumpkin puree by pressing it on paper towels to remove excess moisture.

Mix the cooled browned butter with granulated and dark brown sugars until it resembles wet sand.

Add egg yolks, vanilla extract, and prepared pumpkin puree, whisking until smooth.

Combine flour, pumpkin spice, baking soda, cream of tartar, and salt in a separate bowl, then fold into the wet mixture.

Form about 3 tablespoons of dough into balls and roll in the cinnamon-sugar mixture before placing on baking trays.

Bake in the preheated oven for 10-12 minutes until edges are golden and centers are puffy.