Optifast VLCD Chocolate Shake can be enjoyed with every meal as part of the Optifast program. It is high in protein, so you feel fuller for longer, and it is also low in calories. How to use: simply add one sachet of Optifast VLCD Chocolate Shake mix to 200ml-250ml of cold water. Stir or shake the liquid until the contents of the sachet are completely dissolved. Do not use boiling water. Add more water if you prefer a larger shake or a diluted flavor. The taste is improved with colder water. You can also vary the flavor and make a mocha shake by adding a teaspoon of coffee granules.