I was first introduced to kefir a few years ago, while on holidays in Greece. This fermented milk drink is not only rich in nutrients, such as protein, calcium and vitamins, but it also contains probiotics. These live micro-organisms (bacteria and yeasts), often described as ‘good’ or ‘friendly’ bacteria, can have various health benefits. For example, they may help sufferers with indigestion, IBS (Irritable Bowel Syndrome) and (rather surprisingly) lactose intolerance. Since kefir has recently become widely available in the UK, I’ve started using it in my recipes as a substitute for yogurt or even milk.     Inspired by the fresh fruit I had whilst island-hopping in the Cyclades…