Slice the tomatoes in half and place cut side up on a lined baking tray

Rub each tomato with a little olive oil and season lightly before placing in an oven at 110˚C/gas mark 1/4 for 6 hours. Alternatively, you could roast the tomatoes for 90 minutes at 130°C/gas mark 1/2, but be aware that this will lessen the taste

After 6 hours the tomatoes should have shrunk but remained juicy inside

Place the olives and garlic in a pan and pour in enough olive oil to cover. Bring to a very gentle simmer and cook until the olives and garlic are very soft

Drain well and then transfer the olives and garlic, along with the capers and anchovies, to a food processor. Gently pulse into a tapenade but do not let the ingredients lose their texture entirely. Finish with a little lemon juice and pepper

Rub the ciabatta slices with olive oil and then chargrill on each side. Rub with garlic and then top each slice with a very thin coating of the tapenade. Top each ciabatta with 3 halves of tomato and 5 basil leaves

Rub the sardines with olive oil before cooking under a hot grill or barbecue for 3-4 minutes. Divide the sardines across the ciabattas and serve