Preheat oven to 350 degrees F (180 degrees C). Lightly grease a 9x13 baking pan and set aside.
In a large bowl combine the flour, sugar, baking powder, baking soda, pumpkin pie spice, cinnamon and salt. Whisk well to incorporate. Add in the oil, pumpkin puree, eggs, vanilla and mix until well combined. Spread into prepared pan. Bake for 25-35 minutes or until a toothpick inserted in center comes out clean. Cool completely before frosting.
In a large bowl or the bowl of your stand mixer combine the cream cheese and butter until smooth. Add the powdered sugar, vanilla and salt and beat for 2 minutes. Spread over cooled cake and top with chopped pecans and cinnamon if desired.