In a large mixing bowl, cream together the vegan butter, pumpkin puree, brown sugar, and granulated sugar until light and fluffy.

In a separate bowl, whisk together the flour, baking powder, pumpkin pie spice, cornstarch, and salt.

Gradually add the dry ingredients to the wet mixture, folding gently until no flour shows.

Cover the dough with plastic wrap and refrigerate for at least 30 minutes.

Preheat your oven to 350°F (177°C). Shape the dough into 2-inch balls and place on a baking sheet.

Bake for 10-12 minutes until edges are set and centers remain soft.

For the frosting, beat together the vegan butter, vanilla extract, cinnamon, pumpkin pie spice, and powdered sugar until smooth.

Once cookies are cooled, frost them and add garnish if desired.