Prepare the vanilla cake according to directions. Pour into 3 greased 6 inch rounds* and bake at 350°F for 30 minutes, or until golden brown and a toothpick inserted into the middle comes out mostly clean. Set aside to chill.
While the cakes cool, prepare the filling. Prepare the caramel according to directions. Set aside 1/2 cup of the caramel to use for drizzling the top of the cake. Add the chopped pecans to the remaining 1 1/2 cups of caramel and stir to combine. Allow to cool down for 15 minutes and then transfer to a piping bag and set aside.
To make the buttercream, beat the butter, cream cheese, powdered sugar, vanilla, and salt, and beat to combine. Scrape down the bowl and beat for 2 minutes until light and fluffy.
To assemble the cake, place the first layer on a cake stand or flat plate. Pipe about half of the caramel praline filling around the cake. Place the second layer on top of the filling and repeat with the remaining half of the filling. Frost the cake with the cream cheese frosting, covering the top and pulling down to cover the sides of the cake. Put the cake in the fridge to chill for 15 minutes. This will help the frosting and filling to set.
While the cake is chilling warm up the remaining 1/2 cup of caramel in a microwave safe bowl. Pour over the top of the cake, letting it drip down the sides. Top the top of the cake with crushed up pecans. Enjoy!