Cut up the rhubarb, chop the dates finely, and mince or finely chop the onions.
Place into a large pan. Add the spices, salt, and sugar, with 285 ml of vinegar.
Simmer gently for at least 2 hours until tender, adding a little more vinegar to prevent sticking.
Add another 425 ml of vinegar and continue simmering until the mixture is thick and leaves no loose liquid when a spoon is drawn through. If the rhubarb is very moist, up to 140 ml vinegar may not be required — reserve this amount until the final test.
Spoon into hot sterilised jars straight away and cover with waxed paper discs and seal with vinegar-proof lids.
Label and store in a cool, dark place.
Notes
Don't forget to tag me on social media! @TheDelectableGarden on Instagram and @TDG.co.uk on FacebookServing amount, costs and nutritional values are for guide purposes only and are based on the ingredients I used. The calorie value is based on a 15g serving.Tips from me!•Leave for 4–6 months to let the flavours develop and the vinegar mellow.•Store in the fridge once opened.•Best served with a VERY strong cheddar 🧀Cook’s Note ⚠️Remember: rhubarb leaves are poisonous and should never be eaten. When trimming your rhubarb, bin the leaves rather than composting them — they contain oxalic acid which is harmful to both people and pets.