Preheat the oven to 350ºF (180ºC) and line 2 large baking sheets with parchment paper.
Add the vegan butter, granulated sugar, and brown sugar to a large bowl and beat until light and fluffy using a hand mixer or a stand mixer fitted with the paddle attachment.
Add the pumpkin puree and vanilla extract and beat on low speed until just combined.
Add the flour, cornstarch, baking soda, salt, cinnamon, and pumpkin pie spice. Beat on low speed until just combined. Do not overmix.
Fold in the vegan chocolate chips by hand using a spatula.
Cover the dough and refrigerate for at least 30 minutes, ideally 1 hour, or until firm enough to scoop easily.
Use a cookie scoop, regular spoon, or your hands to portion about 2 tablespoons of dough per cookie. Scoop the dough onto the lined baking sheets, spacing the cookies about 2 inches (5 cm) apart. Gently flatten each one with your hands.
Bake for 10-12 minutes, or until the edges are set and lightly golden and the centers still look soft. Let the cookies cool on the baking sheet for 10 minutes before transferring them to a cooling rack; they’ll firm up as they cool.
Notes
Store the cookies in an airtight container at room temperature for 3-4 days.
Keep them refrigerated in an airtight container for up to 1 week.
Freeze baked cookies in a freezer-safe container or bag for up to 3 months.
Thaw frozen cookies at room temperature before serving.
Microwave for 10-15 seconds if you want them soft and warm again.