Preheat your oven to 350° F and grease TWO 9x13" baking pans with Pam cooking spray.
In a large bowl, combine the gluten-free flour blend, baking powder, baking soda, cinnamon, and Kosher salt. Whisk together until well mixed.
In another bowl, whisk together the eggs, sugar, oil, and pumpkin puree until well combined.
Carefully add your dry ingredients into the wet mixture. Stir until everything is just combined.
Divide the batter evenly between the two prepared baking pans. Bake for about 25–30 minutes. Allow the cakes to cool completely before frosting.
In a mixing bowl, beat together softened cream cheese, butter, vanilla extract, and powdered sugar until smooth and creamy.
Spread the cream cheese frosting evenly over each cooled pumpkin cake before cutting them into squares.