Preheat your oven to 350°F. Prepare a 12"x17" half-sheet pan by lining it with parchment paper and spraying the sides with cooking spray.
Using an electric mixer or a large bowl, cream together the softened butter and granulated sugar. Once fluffy, add the eggs and blend until well mixed.
In a separate bowl, sift together the all-purpose flour, salt, ground cinnamon, baking soda, and baking powder. Gradually add this dry mixture to the wet ingredients in the mixer, blending well.
Fold in the pumpkin puree until fully incorporated.
Pour your batter into the prepared pan and bake for 20-25 minutes or until a toothpick inserted into the center comes out clean.
While the bars are baking, prepare the cream cheese frosting. In a stand mixer or using a hand mixer, combine the softened cream cheese, butter, and vanilla extract.
Slowly mix in the powdered sugar, adjusting consistency as needed by adding a tablespoon of milk at a time if it’s too thick.
Once the bars are cool, spread the cream cheese frosting evenly over the top. Slice into bars and enjoy!
They can be stored in an airtight container in the fridge for up to 5-6 days or frozen for 3 months.