How to make rhubarb ketchup – recipe

Last week I was given a great big bundle of homegrown rhubarb stalks, all beautiful green and magenta, so I've been making use of it in all ways imaginable.

And then we ran out of ketchup – something of a crime, given how much my children love the stuff. There was an obvious solution at hand: rhubarb ketchup. Ketchup needn't be the red stuff from a squirty bottle. The word ketchup (or, to give it an even quainter name, catsup) refers to a sweet and tangy sauce to serve at the table as a condiment. Mushroom, anchovy, tomato … why not rhubarb?

Fruity, tart and very juicy, rhubarb can ape all the qualities that make tomato a classic ketchup ingredient.

(Makes 2 x 450g jars)
700g rhubarb, roughly chopped into 1in batons
1 large white onion, diced
3 fresh bay leaves
10g fresh ginger, roughly chopped
3 whole star anise
4 whole allspice berries
1 teaspoon caraway seeds
100ml red/white wine/cider vinegar
100ml water
100g sugar
1 teaspoon of salt

Heat the oven to 180C/350F/gas mark four. Spread out the rhubarb, onion, bay leaf and ginger in an even layer on a baking tray.

Bake for about 45 minutes, checking from time to time and stirring so it doesn't catch. Remove when the rhubarb and onions are very soft and broken down.

Meanwhile, toast the star anise, allspice and caraway in a dry frying pan until fragrant. Pound in a pestle and mortar or blitz in a spice grinder.

Blitz the cooked rhubarb mixture, complete with bay leaves and ginger, to a fine pulp in a blender or food processor.

In a saucepan over moderate heat, add the rhubarb pulp, vinegar, water, sugar, salt and ground spices.

Bring to the boil, reduce to a simmer and cook 15-20 minutes until you achieve your desired consistency. Stir frequently so the ketchup doesn't catch on the pan. Pass through a fine sieve, if you like (I didn't bother).

Pour the ketchup into sterilised jars and seal.

Sealed well, this ketchup will keep indefinitely. Once opened, store in the fridge and use within a month.

Serve as you might tomato ketchup or, as here, in a cheese sandwich.