In a mixing bowl, whisk together the flour, salt, pumpkin spice, and baking powder.
Place the softened butter, sugar, and brown sugar in the bowl of a stand mixer. Whip until light and fluffy.
Mix in the eggs, vanilla, and pumpkin puree.
Add the dry ingredients to the butter and sugar mixture and stir to combine.
Place a sheet of parchment paper on a 9x13 jelly roll pan with the edges hanging over the sides.
Spread the cookie dough over the parchment paper and bake at 350 degrees for 25-30 minutes. Remove the cookies and allow them to cool completely before frosting.