In a large bowl, mix together the flour, cocoa powder, baking powder, baking soda, and salt together.
In a separate bowl, beat together room temperature eggs, granulated sugar, brown sugar, vegetable oil, and vanilla.
Pour the wet ingredients into the dry ingredients.
Combine hot water and the 2 teaspoon of instant coffee until dissolved. Add to bowl.
Add in the buttermilk and stir together the ingredients until just combined. Don't over mix.
Fill the cupcake liners about ¾ of the way full and bake in the oven for 14-16 minutes. Check the center with a toothpick to see if they're done. (The center will come out clean)
Allow the cupcakes to cool completely before frosting.
Salted Caramel Frosting
Beat together the softened butter until creamy.
Add in the vanilla extract.
Beat in the salted caramel sauce.
Beat in the powdered sugar slowly.
Add in the ¼ cup half & half a little at a time until desired creaminess is achieved. Add more if you want it more creamy.