Peel and roughly chop your pears. Discard the cores and stems. Pop into a food processor or blender with a squeeze of lemon juice and the powder from your sachet of saffron. Blend till smooth, trickling in 400ml cold water (or more) to reach the taste and texture you want.
TIP: leftover smoothie? Whisk in a little honey to sweet and freeze in ice lolly moulds for a refreshing healthy treat.