Mix together the butter and sugar in a large mixing bowl.
Add the egg and vanilla extract, then mix in the flour, baking powder and salt.
Once the mixture is combined, add the roughly chopped chocolate chips.
Half-fill the shot glass cookie moulds with cookie mixture, then insert the middle section and push down until the inner section is sticking out by just 5mm.
Trim any spare biscuit mix that pushes out of the top of the mould.
Bake the cookies for 20-25 minutes until well cooked.
Trim any cookie mix that has come over the top of the mould then leave to cool in the tins for 10 minutes - no longer, as the chocolate will start to set and stick .
Carefully turn the tins upside down to release the cookies from the moulds.
Once cool, pour the chocolate into the cookie cups and move around the cover the inside of the cups to create a water-tight lining.
Leave to set for at least one hour before using as a liquid container.
Slice the banana into thin slices and lay on a baking sheet. Sprinkle with brown sugar and then, using a blow torch, caramelise the sugar.
Cocktail & Serve
Mix equal parts dark rum, banana liqueur and cream together and shake over ice.
Serve in the cookie shot glasses with a squirt of cream and grated chocolate.