Preheat the oven to 350ºF. Grease a 10x15 inch baking pan with cooking spray.
In a bowl, mix together flour, baking powder, cinnamon, pumpkin pie spice, and salt. Set aside.
In a large mixing bowl, beat together eggs, granulated sugar, and light brown sugar using an electric mixer until smooth. Then, add pumpkin puree, oil, maple syrup, and vanilla extract. Beat until combined.
Sprinkle the dry ingredients over the wet ingredients. Stir carefully using a rubber spatula until just combined and no big lumps of flour remain.
Pour the pumpkin batter into the prepared baking pan and spread evenly.
Bake for 25 minutes until the toothpick inserted in the center comes out clean. Remove from the oven. Let cool completely before frosting.
Meanwhile, prepare the cream cheese frosting. In a mixing bowl, combine cream cheese and butter, using an electric mixer, until creamy. Add vanilla extract and salt, beat to combine. Gradually add the powdered sugar and beat on low after each addition until smooth and fluffy.
When the pumpkin bars are already cooled, spread the cream cheese frosting on top. Slice into 24 bars and serve. Enjoy!