Measure ½ cup (120g) pumpkin puree. Spread on a double layer of paper towels or a clean kitchen towel.
⅓ cup blotted pumpkin puree
Fold the towel over and gently press to remove excess liquid. Repeat this process multiple times to remove excess water from the pumpkin puree. Once thickened and matte, measure ⅓ cup (75g-80g) for the recipe.
Brown the butter
In a saucepan over medium heat, melt the butter. Stir constantly as it foams, then turns golden brown with a nutty aroma (5–7 min).
¾ cup unsalted butter
Pour into a large mixing bowl and let cool the brown butter cool down in the fridge for 20-30 minutes stirring from time to time. You want the brown butter to almost have the texture of your favorite face cream. Not fully solid, but not liquid either.
Mix the wet ingredients
Whisk both sugars into the cooled brown butter until smooth.
⅔ cup dark brown sugar, ⅓ cup granulated sugar
Mix in the egg yolk, blotted pumpkin puree, and vanilla until well combined.
1 large egg yolk, 1 ½ tsp vanilla extract
Combine dry ingredients
In a separate bowl, whisk together the flour, baking soda, cream of tartar, salt, pumpkin pie spice, and cinnamon.
1 ½ cups all-purpose flour, ½ tsp baking soda, ½ tsp cream of tartar, ½ tsp salt, 2 tsp pumpkin pie spice, ½ tsp ground cinnamon
Make the dough
Gently fold the dry ingredients into the wet mixture until just combined.
Preheat to 350°F and line baking sheets with parchment paper. Scoop 2 tbsp mounds of dough or about 41 grams of dough. Roll each mound lightly in the cinnamon-sugar topping.
3 tbsp granulated sugar, 1 tsp ground cinnamon
Place 3 inches apart on the baking sheet.
Bake 9-10 minutes, until edges are set and centers look slightly underdone.
Let cookies cool on the pan for 5 minutes, then transfer to a wire rack.