Pumpkin Cake:
Preheat the oven to 350°F (175°C). Grease and flour a 9×13 inch baking pan.
In a medium bowl, whisk together the flour, pumpkin pie spice, baking powder, baking soda, and salt.
In a large bowl, beat the oil, brown sugar, white sugar, eggs, vanilla extract, and pumpkin puree until smooth.
Gradually add the dry ingredients to the wet mixture, beating in about half at a time. Scrape down the sides of the bowl as needed.
Pour the batter into the prepared pan and bake for 35-40 minutes, or until the cake is firm to the touch and a toothpick inserted comes out clean. Let the cake cool completely before frosting.
Caramel Cream Cheese Frosting:
In a large bowl, beat the softened butter until smooth and creamy.
Beat in the cream cheese until fully combined and smooth.
Gradually mix in 1 1/2 cups of powdered sugar, followed by the salted caramel sauce.
Continue adding the remaining powdered sugar, 1/2 cup at a time, until the frosting reaches your desired sweetness and consistency.
If the frosting becomes too thick, add 1-2 tablespoons of whipping cream to loosen it. Set aside.
Salted Caramel Sauce (Optional):
In a large saucepan, melt the sugar over medium heat, whisking constantly. It will form clumps before turning into a smooth amber-colored sauce.
Whisk in the butter until fully melted. Remove from heat and whisk in the whipping cream, vanilla extract, and salt. Let it cool slightly before using in the frosting.
Assemble the cake by spreading the caramel cream cheese frosting evenly over the cooled pumpkin cake. Serve and enjoy!