Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.
In a medium bowl, whisk together the flour, baking soda, baking powder, cinnamon, nutmeg, and salt. Set aside.
In a large bowl, cream together the softened butter, brown sugar, and granulated sugar until light and fluffy, about 2-3 minutes.
Beat in the egg, pumpkin puree, maple syrup, and vanilla extract until well combined.
Gradually add the dry ingredients to the wet ingredients, mixing until just combined. If using, fold in the chopped nuts and chocolate chips.
Drop rounded tablespoons of dough onto the prepared baking sheet, spacing them about 2 inches apart.
Bake for 12-15 minutes, or until the edges are lightly golden. The centers may look slightly underbaked; they will firm up as they cool.
Allow the cookies to cool on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely.