Playworkers will need some picnic ideas for the summer. Kids cookery expert Fiona Hamilton-Fairley lays a bet that these should please most children. at the Kids Cookery School in west London, which I run, we often find that some of the simplest recipes are the most endearing. At a summer park workshop a few years ago, we made some chicken and ham roll-ups for our picnic. A little lad, still smacking his lips, told me how much he'd liked the food - 'but don't tell mum how easy it was, otherwise she'll stop making me tea in the evening.' Of...