Store in the fridge in a plastic bag to retain moisture.
Steam or boil it for 3-5 mins, depending on the variety (red russian kale cooks quickest, black kale takes the longest).
Separate the leaves from any tough stems, either cook them for a min or two longer (Red Russian), or if they are very bitter (curly or black kale), discard the stalks.
Try braising instead of boiling – add kale to a pan with a knob of butter, a little water, grated nutmeg and lemon juice, or fry a little onion and garlic in oil, add chilli, kale, and a little water or stock. Cook for about 5 mins or so, until tender. Stir in cooked lentils or beans if you like.
Kale goes well with similar things to cabbage: chilli, garlic, caraway and pork, particularly chorizo.
Add to soups or stews, it’s also good in risottos or pasta. Try mixing cooked kale with mashed potato as a side dish or pie topping.