Salted Caramel Cake with Kentucky Buttercream

*ingredients:
°3 cups/13 1/2 ounces flour (all purpose)
°2 cups sugar (granulated)
°1 teaspoon of salt
°1 teaspoon baking powder
°1/2 teaspoon baking soda
°1 c butter (room temperature)
°2 t vanilla
°4 eggs
+sauce
°3/4 c sugar
°1/3 c butter
°3 tsp of water
°2 tsp vanilla
*How to make e: