Combine the chillies, onion and garlic in a food processor. Process until very finely chopped. Transfer to a medium, heavy-based saucepan.
Add the tomatoes, salt, sugar, vinegar, port and water. Stir over medium heat for 6-8 minutes or until the sugar has dissolved. Increase the heat to medium-high and boil gently for 40-45 minutes until thick and jam-like. Spoon into a sterilised jars, seal and allow to cool.
TipThe kumato® chilli jam will keep for 4 months in the fridge. Use on sandwiches, pizzas, ploughmans lunch, or serve in a bowl on a cheese board or antipasto plate.