Preheat the oven to 325°F.
Adjust the oven rack to lower-middle position. Line a 9X13-inch baking pan with foil, letting the excess hang over the edges of the pan by about 1 inch so you can grab those edges and pull the bars from the pan after they have baked. Spray foil so pan is well greased.
Mix the flour, salt, cinnamon, and baking soda together in medium bowl; set aside. Whisk the melted butter and sugars in a large bowl until combined. Add the pumpkin and vanilla and mix well. Using a rubber spatula, fold the dry ingredients into the wet mixture until just combined; do not over-mix. Fold in the chocolate chips and turn the batter into the prepared pan, smoothing the top with the spatula.
Bake until the top of the bars is light golden brown, and edges start pulling away from sides of pan, 24-26 minutes. (Note these take longer than the traditional cookie bars because of how moist the pumpkin is.) Make sure the top is firm before removing from oven.
Cool pan on a wire rack to room temperature. Once cooled, remove the bars from the pan by lifting the foil overhang and transfer them to a cutting board. Cut into squares and serve.
