For chewy cookies, you'll want to remove as much water from the pumpkin purée as possible - please don't skip this step or the recipe won't work! Start by spreading the pumpkin purée into a thin layer on a small plate. Then, press a paper towel to the top of the pumpkin purée to soak up as much liquid as possible. Repeat this process 2-3 more times, until the pumpkin is dry and reduced by half. You should have 30 grams of dried pumpkin purée.

Then, add the melted butter and brown sugar to a medium mixing bowl. Whisk until the mixture starts to pull away from the sides of the bowl, about 1 minute. Mix in the egg yolk, vanilla extract, and dried pumpkin purée until smooth.

Add the flour, cornstarch, pumpkin pie spice, cinnamon, ginger, cloves, allspice, baking soda, and salt. Mix just until there are no more streaks of flour. The dough will be loose. Cover the bowl and freeze or refrigerate the dough for 30-60 minutes, until it's cold enough to scoop.

Preheat the oven to 350°F (177°C). Line a sheet pan with parchment paper. Then, combine the granulated sugar and pumpkin spice or cinnamon in a small, shallow bowl to make the spiced sugar.

Once the dough is chilled, use a scoop to divide the dough into 6 balls. Roll each cookie dough ball in the spiced sugar. Pat the cookie dough balls into thick puck shapes.

Place the cookies 2-3 inches apart on the prepared sheet pan. Bake for 12-14 minutes, until the edges are set and the centers are still a bit under-done. Let the cookies cool on the sheet pan for 5 minutes and then transfer the cookies to a wire rack to cool completely. Enjoy!