Mix 1 1/4 cups hot water with 1 Via Coffee packet.
Make cupcakes according to box directions except use coffee in place of water.
Transfer to wire racks to cool.
Cut a small square in the top of each cupcake and remove a chunk from the middle of the cupcake.
Pour a small amount of caramel sauce into the middle of each cupcake.
Place the top of the "plug" back on each hole.
Cream butter and 1 packet of Via in a medium bowl.
Slowly add in the powdered sugar, and milk as needed, until everything is incorporated and frosting is right consistency.
Transfer to piping bag or zippered bag and clip corner to pipe.
Ice each cupcake and drizzle tops with caramel sauce.