Thinly slice the red onion. Deseed, then finely chop the chilli.
In a heavy-based sauce saucepan, heat the oil, then gently sauté the onion and chilli for about 5 minutes until the onion has softened. Stir in ginger for a minute or so.
Add the cherries, sugar, cider vinegar, lemon juice, raisins and salt. Bring to the boil, lower the heat and simmer (under cover) for about 30 minutes until the sauce thickens to jam-like consistency.
Let it cool.
When cooled, transfer to a sterilised, cooled jar and store in a cool place.
After opening, store in the fridge.