Preheat oven to 350 degrees Fahrenheit. Line a 12"x17" half-sheet baking pan with parchment paper. Spray the sides of the pan with cooking spray. This size gives a slightly shorter bar about ¾" thick after baking, like I have in the photos above.Note: You can also use a 10"x15" jelly roll pan for a slightly taller bar.
Cream together butter and white sugar in an electric mixer or large mixing bowl. Add eggs and mix well.
Sift together flour, salt, cinnamon, baking soda, and baking powder. Slowly add dry ingredients to the mixer. Blend pumpkin puree into batter.
Pour batter into the prepared jelly roll pan. Bake in the oven for 20-25 minutes until a toothpick comes out clean.
While the bars bake, make the cream cheese frosting.
In a stand mixer or a large bowl with a hand mixer, blend together cream cheese, butter, and vanilla extract.
Slowly begin adding powdered sugar and blend well. Slowly begin adding powdered sugar and blend well. If too thick, add 1 tablespoon of milk at a time until desired consistency. If it's too thin, add more powdered sugar.
Spread cream cheese frosting over cooled bars evenly. Slice before serving. Store in an airtight container in the refrigerator for up to 5-6 days or freeze for up to 3 months for best quality.
