1. Preheat the oven to 325 F and prepare (3) 8″ baking pans* by spraying them thoroughly with nonstick spray then lining them with a circular parchment round, and lightly flouring them. Set aside.
2. In a large mixing bowl, sift together the flour, baking powder, baking soda, pumpkin pie spice and salt. In the bowl of a stand mixer fitted with the paddle attachment, add the butter and both sugars, then mix on high for 2-3 minutes or until light and fluffy. With the mixer running on low, add the eggs, one at a time, followed by the oil. Add in the pumpkin puree, then mix just until combined. Remove the bowl from the stand mixer, then fold in the dry ingredients using a spatula until there are no visible dry streaks remaining. 
3. Divide the batter evenly among the prepared cake pans, using a kitchen scale if desired. Bake the cakes for 18-20 minutes, or until a toothpick inserted in the center comes out clean. Cool the cakes for 10 minutes before inverting them on to a wire rack to cool completely before frosting.
4. Prepare the frosting. In the bowl of a stand mixer fitted with the paddle attachment, beat the butter and cream cheese on medium-high until light and fluffy. Add in half of the powdered sugar, along with 1 tbsp of heavy cream, and mix to combine. Add the vanilla, salt and salted caramel and the remaining powdered sugar and mix on high until light and fluffy. If it’s too stiff, add the remaining tablespoon of cream. If the frosting is too runny, add in a bit more powdered sugar until your desired thickness is reached!
5. Frost the cake layers, one at a time. Top the cake with additional caramel sauce, chopped pecans, and caramel pieces as desired. Enjoy!

Prepared cake can be kept at room temperature, covered, for 1-2 days, or in the fridge, covered, for 3-4 days. Unfrosted cake layers can be stored in the freezer, tightly wrapped in plastic wrap for up to 2 months. Thaw overnight in the fridge.