Heat oven to 140C/120C fan/gas 1. Wash your jars in warm soapy water and rinse well. Place on a baking sheet and put in the oven to dry completely. If using Kilner jars, boil the rubber seals as dry heat damages them.
Put the garlic, chilli and ginger in a food processor and pulse until blended. Add the tomatoes and pulse until finely chopped. Pour into a saucepan and add the sugar, cider vinegar and the spices. Bring to the boil, then turn down to a simmer. Cook for 45 mins or until thick and syrupy. Pour into sterilised jars with fitted lids. Will keep chilled for 1 month.
Serve the chilli jam with toasted baguette slices and a sharp firm cheese like Manchego or goat’s cheese.