Preheat the oven to 100ºC/210ºF/gas ¼. Halve the tomatoes and lay them cut-side up in two baking trays. Sprinkle lightly with sea salt. Peel and finely slice the garlic, then fleck a couple of garlic slices onto each tray. Drizzle the lot with olive oil. Pop in the oven for 4 hours, or until soft and sticky. Remove from the oven and leave to cool. Roughly chop and scatter with a few herbs, then layer up the tomatoes in sterilised jars. Top up with extra virgin olive oil to cover, pop the lids on and keep in the fridge where they’ll sit for up to 2 weeks.