1. To make the cookies, Preheat the oven to 160°C.
2. Place 1 cup of the chocolate, peanut butter and coconut oil in a heatproof bowl over a saucepan of simmering water and stir until the mixture is melted and smooth. Set aside.
3. Place the egg, sugar and vanilla in the bowl of an electric mixer and whisk for 10 minutes or until pale and creamy.
4. Stir through the chocolate mixture, protein, cacao, baking powder and salt and remaining chocolate into the egg mixture.
5. Spoon tablespoonfuls of the mixture, at a time, onto baking trays lined with non-stick baking paper. Bake for 8–10 minutes or until puffed and cracked. Allow to cool completely on trays
6. Mix the water and Lunar Latte together until combined. Ripple through the ice cream, then spoon onto the biscuit to make the sandwiches.