Preheat the oven to 350°F and line two large baking sheets with parchment paper.

Place the butter in a medium microwave-safe bowl and heat until melted. Allow it to cool slightly.

Add the pumpkin puree, granulated sugar, brown sugar, molasses, and vanilla extract to the melted butter.

Whisk until the ingredients are thoroughly combined.

In a separate mixing bowl, whisk together the flour, pumpkin pie spice, baking soda, and kosher salt.

Gradually add the dry ingredients to the pumpkin mixture, stirring until a soft cookie dough forms. Avoid overmixing once the flour has been incorporated.

Fold in the semi-sweet chocolate chips and dark chocolate chunks until they're evenly distributed throughout the dough.

Using a medium cookie scoop, portion the cookie dough into your hands and gently roll each portion into a ball.

Arrange the cookie dough balls on the prepared baking sheets, leaving space between them.

Using your fingertips, gently press each ball into a thick disk.

Pumpkin cookie dough doesn't always spread as much as traditional chocolate chip cookie dough, so this step helps the finished cookies bake into the right shape.

Continue until you've used all of the dough.

Bake at 350°F for 13–15 minutes, or until the cookies appear set and the centers no longer look wet or gooey.

Be careful not to overbake them. The cookies will continue to set as they cool.

Allow the cookies to cool on the baking sheet for several minutes before transferring them to a wire cooling rack.

Cool completely and enjoy.