Plum ketchup

Heat the oil in a large saucepan over a low heat. Add the onion and celery and fry for 8 minutes, until softened. Add the garlic, ginger and spices and heat for another 4-5 minutes, until lightly golden and fragrant.

Add the plums, salt, sugar and vinegar and 300ml water. Bring to the boil, cover and simmer for 30 minutes, until the plums have all broken down.

Remove the lid and continue to bubble for another 30 minutes, stirring frequently, until thickened.

Use a stick blender to blitz the ketchup until smooth, then push through a fine sieve. Loosen with a little extra water, if needed, then pour or spoon into a sterilised glass jar or bottle. Keep in the fridge for up to 4 weeks.