1 kg fresh ripe or frozen tomatoes
Chop the whole fresh or frozen tomatoes into small dice and set aside.
Cut off the stems and roughly cut up the chillies. Remove the skin and roughly chop the ginger. Peel the garlic cloves.
800 g canned plum tomatoes, 4 red chillies with their seeds, 2 green chillies with their seeds, 10 garlic cloves, 110 grams fresh root ginger, 80 millilitres Thai fish sauce
Put the tinned tomatoes into the food processor with the chillies and their seeds, garlic, ginger and fish sauce and blitz into a fine puree.
675 grams granulated sugar, 200 millilitres red wine vinegar
Spoon the puree into a deep, heavy-bottomed pan and add the sugar and wine vinegar.
Bring to the boil slowly, stirring as you go. When it comes to the boil, turn down to a simmer and add the diced tomatoes.
Skim off any foam that rises to the surface and cook gently for up to 1 1/2 hours, stirring from time to time, to prevent the mixture catching and burning. Scrape the sides of the pot too, so that everything cooks evenly. The mixture thickens as it cooks - as it reduces and the pectin in the tomatoes takes effect
When the mixture seems thick to the stir of a wooden spoon.
Use a ladle or jug to pour it into warm, sterilised jars and seal.