Preheat the oven to 350F. Butter and flour a 9x13-inch cake pan or spray with baking spray with flour.

In a large bowl, sift together the flour, baking powder, baking soda, cinnamon, ginger, nutmeg, and salt.

In a separate bowl, whisk together the granulated sugar, pumpkin, oil, eggs, and vanilla, until smooth. Pour into the flour mixture and stir together just until combined. Pour into the prepared cake pan.

Bake for 30 minutes or until a toothpick inserted into the center comes out with a few crumbs. Let cool completely on a wire rack.

In a large mixing bowl or the bowl of a stand mixer fitted with the paddle attachment, beat the butter until smooth. Add the cream cheese and beat on medium-low speed until the mixture is well combined, about 2 minutes. Scrape down the bowl as needed. Beat in the vanilla and salt.

With the mixer on low speed, slowly add in the confectioners’ sugar. Once incorporated, increase the speed to medium and beat until light and fluffy, about 1 minute. Spread over the top of the cooled cake.