In a large mixing bowl, cream together vegan butter, pumpkin puree, granulated sugar, brown sugar, and vanilla extract until light and fluffy, about 3–4 minutes.

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

Gradually add the dry ingredients to the wet mixture, stirring gently until just combined.

Cover the bowl and refrigerate the dough for at least 30 minutes.

Preheat your oven to 350°F (177°C) and line a baking sheet with parchment paper.

Scoop out 2-inch balls of dough and place them on the baking sheet, flattening each slightly.

Bake for 10–12 minutes, until edges are set but centers are soft.

Let the cookies rest on the baking sheet for about 5 minutes before transferring to a cooling rack.

In a medium bowl, beat together vegan butter until creamy.

Gradually mix in powdered sugar, ground cinnamon, and non-dairy milk to reach desired consistency.

Frost cooled cookies generously with the creamy cinnamon frosting.