Measure pumpkin puree, then place in a paper towel lined bowl. This will reduce the moisture in the pumpkin. Let the pumpkin sit for 20 minutes before using.
Preheat oven to 350° F. Line 1-2 baking sheets with parchment paper and set aside.
In a large mixing bowl, add the flour, baking powder, baking soda, pumpkin spice, and salt. Mix well.
In the bowl of a stand mixer, add the room temperature butter, sugar, and brown sugar. Cream together using the paddle attachment until it is light and fluffy, or about 2 minutes. Add the egg yolks and pumpkin puree, then mix to combine.
Add the flour mixture to the butter mixture and mix on low speed until the cookie dough is combined. Fold in the white chocolate chips last.
Use a small ice cream scoop or a spoon to scoop and roll all of the dough into 1" - 1¼" dough balls. Place about 2" apart on the prepared baking sheets.
Bake in a preheated 350-degree oven for 8-10 minutes, or until golden brown on the edges.
Remove the cookies from the oven and let them cool on the baking sheet for a few minutes, then transfer to a wire rack and let them cool completely. Enjoy!