A lassi is simply a cooling, whisked yoghurt drink. For the best lassi select the best yoghurt – this is essential. A good lassi is not good enough with light yoghurt or fat-free yoghurt. In India, buffalo milk is normally used which yields approximately 10–12 percent fat. You do not have to go to that extent as then the lassi becomes heavy but, ideally, use whole milk yoghurt or a low-fat Greek-style will do if you are watching your fat content. Lassi can be either sweet or savoury. For a lighter, thinner lassi, use half yoghurt and half milk.