Preheat your oven to 350 degrees F. Place parchment paper on two baking trays and put them aside.

Use a stainless steel pan to brown the butter over medium heat. Once it starts to pop and form a foam, stir occasionally so as not to burn. Remove the pan from the heat when you smell a nutty aroma and the color turn golden brown.

Pour your browned butter into a heat-proof measuring cup (you should have 1 cup) and sit in the fridge for about 45 to 60 minutes (stir every 20 min). When you check with a thermometer, it should read 70 to 75 F (the temperature shouldn’t be warmer or it’ll cause the cookies to flatten).

Layer the pumpkin puree on a plate and use paper towels to soak up the extra liquid. Repeat this process until the pumpkin puree feels pretty dry (it should be like soft playdough). Measure about 1/3 cup.

Once your butter is cool enough, mix the granulated sugar and brown sugar for 1 minute. (it should have wet sand texture).

Whisk together the vanilla, egg yolks, and the dried pumpkin puree.

Combine the flour, pumpkin spice, salt, cream of tartar, and baking soda until you form dough, then let it chill in the fridge for about 5 minutes or until it firms up a bit.

While the dough is sitting in the fridge, take a small bowl and mix in the cinnamon and 1/3 cup of granulated sugar.

Remove the cookie dough from the fridge, scoop into 3 tablespoon-sized balls, roll each ball through the cinnamon sugar then transfer into the previously prepared baking sheets, spacing at 2 to 3 inches apart.

Bake for 10 to 12 minutes or until the edges turn golden brown. Let your cookies cool completely before serving or storing for later.