The twist is that with the EspressoGC you can make the espresso directly using Tonic Water. This allows for a beautifully unique taste as the tonic is infused with the espresso through the brewing process. The added CO2 from the tonic water also leads to an amazingly thick crema from the espresso machine.
Simply fill & prepare your portafilter basket like you would for a double espresso shot. Instead of pouring hot water into the top, use cold Tonic Water. Raise the arms and pull your shot as normal. Add ice and top up with more tonic as required (or not!).
Try experimenting with any, yes any carbonated drink. Coca Cola, Lemonade, Beer....... The added carbon dioxide (soda) creates interesting crema !!