BBC Good Food Cheese Club
Read about the all-new BBC Good Food Cheese Club. Curated cheese, delivered straight to your door.
Slice the tomatoes (you can skin them if you want, but it's not necessary). Finely chop the onions. Layer both in a large bowl with the salt. Leave overnight.
The next day, chop the sultanas using a large, sharp knife, then peel, core and chop the apples. Put the sugar and vinegar into a large pan and bring to the boil, stirring to dissolve the sugar. Add the sultanas and apples and simmer for 10 mins. Strain the tomatoes and onions in a colander (but don’t rinse), then tip into the pan and return to the boil.
Simmer for about 1 hr, stirring occasionally until the mixture is thick and pulpy. Transfer to warmed jars (see tips, below) and cover with lids.