Rhubarb and rosemary ketchup

If you have run out of tomato and plum ketchups by early spring, this rhubarb version will restock your cupboards nicely. You can make it with forced or unforced stems, and it is a good recipe for using up less tender shoots, but the pinker the stems the pinker the ketchup. The rosemary pairs beautifully with the rhubarb to create a savoury, sweet-and-sour sauce.