Preheat oven to 180 degrees C. Line 2 baking trays with baking paper.
Combine the currants and coffee liqueur in a small saucepan; bring to a simmer over medium heat then remove from heat immediately.
Pour water into a saucepan until about 3cm deep and place over low heat. Place a stainless steel bowl over the saucepan to form a double boiler. Combine the dark chocolate and butter in the bowl then heat and stir just until the chocolate melts; set aside.
Stir together the flour, baking powder, salt, cinnamon, black pepper and cayenne pepper in a bowl; set aside.
Whisk the eggs and sugar together in a separate large mixing bowl until light and fluffy and pale yellow in colour, about 5 minutes. Add the vanilla essence; stir. Beat the melted chocolate into the egg mixture until well combined. Pour the currants and chocolate bits into the mixture; then fold in the flour mixture and stir until evenly combined. Scoop 2-tablespoon portions onto the prepared baking trays with enough space between so they do not run together.
Bake in the preheated oven until barely set, about 12 minutes. Allow to cool on the sheets until they set slightly, about 5 minutes, before transferring to a rack to cool completely.