Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.
In a large mixing bowl, whisk together the melted butter, granulated sugar, and brown sugar until well combined.
Add the pumpkin puree, egg, and vanilla extract. Stir until smooth and the mixture is thoroughly combined.
In a separate bowl, whisk together the flour, baking soda, baking powder, cinnamon, nutmeg, and salt.
Gradually add the dry ingredients to the wet ingredients, stirring gently just until combined. Be careful not to overmix, as this can affect the cookies’ texture.
Fold in the semi-sweet chocolate chips and dark chocolate chips (if using).
Drop spoonfuls of the cookie dough onto the prepared baking sheet, spacing them about 2 inches apart. Top each cookie with a few extra chocolate chips for that gooey, melty chocolate appearance.
Bake the cookies for 12-14 minutes, or until the edges are lightly golden but the centers remain soft and gooey.
Allow the cookies to cool on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely.
