Usually one takes a bottle of wine or sparkling water but when it comes to the cook it's a little more difficult, especially if he / she does not enjoy cooking and therefore deserves a spoiling. One can stick with chocolates or flowers which are always winners or one can take a little more trouble and give something wholly unexpected.
One can buy a Kerneels & Kie novelty boxe and fill it with something he / she would like - a carved wooden mouse for the cheeseboard perhaps, a beaded bracelet, ear rings, a luxury cream, a jam spoon (which is marvellous because it means no butter in the jam) or a pretty lavendar bag for the linen cupboard. You'll know what your friend would like.
... and one thing more we can assure you from experience, people do love our novelty boxes.