I don’t know whether it’s down to the weather this year – very wet spring and weeks of hot and dry conditions during the middle of summer – but my curly kale is doing incredibly well. I love having it instead of cabbage to complement a roast dinner with loads of roast potatoes and parsnips and oodles of gravy It takes no more than 5 minutes to cook on the hob in a few spoonfuls of simmering water. But surely there must be more to this pretty, frilly leafed green vegetable