Preheat oven to 350 degrees F.

In a large bowl, beat together butter and sugar until light and fluffy. Add in eggs and vanilla, mixing well to combine. In a separate bowl, combine flour, cocoa powder, baking soda, baking powder and salt. Add half a dry ingredients to wet ingredients and mix well to combine, followed by half of buttermilk, mixing well to combine beating well after each addition. Add remaining dry ingredients, mix well, and finish with remaining buttermilk, mixing well to combine.

Line muffin pans with liners, and fill with batter, about 2/3 of the way full. If desired, top each cupcake with a pinch of sea salt prior to baking. Bake for approximately 15-20 minutes or until cupcakes spring back when lightly touched and/or toothpick inserted into the center comes out clean. Remove from oven and allow to cool completely prior to frosting.

Cream together butter and peanut butter until well blended and creamy. Add in caramel sauce and mix well. Add in powdered sugar, beating well, slowly adding in whipping cream until your desired consistency is reached. Beat for approximately two minutes. Add to cupcakes by piping or spreading. Top with a sprinkle of sea salt, a drizzle of caramel and truffles, if desired.