Place the butter (226g) and sugar (135g) in a saucepan and heat over a low heat until the butter is melted.

Remove from the heat and stir in the vanilla extract and allow to cool for 15 minutes.

Stir in the egg, flour (281g) and cocoa powder (25g) and mix until combined.

Stir in the chopped pistachio nuts (90g).

Divide the dough in half and wrap in plastic wrap and chill for 30 minutes.

Preheat the oven to 400ºF / 200ºC degrees.

Line several cookie sheets with parchment paper.

On a floured surface, roll out one half of the dough to ¼ inch thickness. Use tree shaped cookie cutters to cut out the shapes and place onto the lined cookie sheets leaving at least one inch between each cookie.

Repeat with the second half of the dough.

Bake for between 8–9 minutes until the edges are firm then transfer to a wire rack to cool.

Melt the chocolate chips (135g) and shortening in a bowl. Dip one edge of each cookie into the melted chocolate then sprinkle over the ground pistachio nuts (60g).