CUPCAKES:

Preheat oven to 350 degrees.

Set up two cupcake tins, with paper liners. (20-24 in total)

Put the cocoa powder in a medium heatproof bowl. Add the boiling water and whisk until a smooth paste forms. This will be thick. Whisk in the buttermilk until combined.

In a separate bowl combine flour, baking soda and baking powder.

With an electric mixer on medium speed, beat shortening with granulated sugar, until light and fluffy.

Add the eggs and vanilla, then beat in the dry ingredients, alternating with the cocoa mixture, until completely combined.

Pour the cupcake batter into the lined muffin cups, filling them about two-thirds full. Bake for 20 to 22 minutes, or until the cupcakes are springy. Let the cupcakes cool in the pans for 5 minutes, then transfer them to wire racks to cool completely.

FILLING:

Beat peanut butter with butter until creamy. Slowly add confectioners sugar until the mixtures is the texture of spreadable frosting. If it becomes too thick, add a small amount of peanut oil to dilute.

Using a pastry bag with a 1/4 star tip, fill bag with peanut butter cream. From the top of the cupcake, push the tip 3/4 of the way into the cake. Squeeze about 1 tblspn cream into cupcake: you should feel the sides of the small cake expand as you squeeze. Place the cupcake back on the wire rack to settle. Save approx 3/4 cup of the filling to decoratively frost cupcakes.

GLAZE:

When all cupcakes have been filled, prepare glaze. In a heatproof bowl, pour the heavy cream. Microwave cream on high for 1 minute or until hot (but not boiling).

Pour the semi-sweet chocolate chips in the hot cream. Make sure all chips are covered with cream. let sit for 5 minutes. Then whisk chocolate and cream into a shiny glaze. Let sit for fifteen minutes or until completely cooled.

Take each cupcake, scrape any filling from top and brush top with a pastry brush to remove crumbs. Dip cupcake into cooled, thickened glaze. Set back on wire rack.

Using remaining peanut butter filling and pastry bag, pip small swirls on each cupcake. Garnish with Hershey square.