Heat oven to 110C/90C fan/gas ¼. Halve the tomatoes and place in a roasting tin with all the other ingredients. Mix everything together with your hands, then arrange the tomatoes in rows, cut-sides up. Roast for 2-2½ hrs, turning the tomatoes over after 1 hr. Can be cooled and kept in the fridge for up to a week.

Tightly pack the confit tomatoes and tray juices into 300ml jars within 1cm of the tops and screw on lids that have been boiled for 10 mins.

Place in a large, heavy-based saucepan with a heatproof plate covering the base. Pour in enough water to cover the jars, then bring to the boil. Reduce the heat and simmer gently for 45 mins. Turn off the heat and leave to cool in the water.

Wipe the jars and store in a cool place for up to 6 months. After opening, use within a week.