Preheat your oven to 350°F (175°C) and line a 9×13-inch baking pan with parchment paper.

In a large bowl, whisk together the pumpkin purée, brown sugar, granulated sugar, egg, vegetable oil, and vanilla extract until smooth.

In a separate bowl, sift together the all-purpose flour, baking soda, pumpkin pie spice, and salt.

Gradually fold the dry ingredients into the wet mixture until just combined, taking care not to overmix.

Stir in most of the semisweet chocolate chips, reserving some for topping before baking.

Pour the batter into the prepared baking pan, spreading it evenly and sprinkling reserved chocolate chips on top.

Bake for 25–30 minutes until the top looks set and a toothpick comes out clean or with a few moist crumbs.

Allow the bars to cool completely in the pan before slicing into squares.