Place the chicken breasts between two layers of greaseproof paper, then bash with a rolling pin until they’re about 1cm thick.
Rub all over with sea salt, black pepper and a little drizzle of oil, then set aside.
Prick 4 chillies, then peel and finely slice 4 garlic cloves. Pick the basil leaves, finely chopping the stalks.
Drizzle a good lug of oil into a medium pan over a low heat, add the pricked chillies, sliced garlic, basil stalks and half the leaves. Cook gently for 15 to 20 minutes, or until softened but not coloured.
Remove the basil leaves (which should be beautifully translucent) and save them for later. Fish out the chillies. Slice them open, scrape out and discard the seeds, then scrape out the flesh and add it to the pan, discarding the skin.
Turn the heat up to medium and add the remaining basil leaves and plum tomatoes. Break them up with the back of a spoon, then allow the sauce to bubble away for at least 20 minutes, or until thickened and the tomatoes have broken down.
Tear up the olives and roughly chop the tomatoes, then add to the pan along with most of the capers. Season to taste.
Place a griddle pan on a high heat and allow it to get super hot. Place the chicken breasts on the griddle and cook for a couple of minutes on each side, or until golden, cooked through.
Finely slice the remaining garlic and fry it in a little oil along with the remaining capers until crispy.
Leave the chicken to rest for a couple of minutes, then slice into long strips. Pour the tomato sauce onto a platter and lay the chicken slices on top.
Deseed and finely chop the remaining chilli, then sprinkle on top along with the garlic and capers. Grate over some lemon zest and Parmesan, top with the rocket and basil leaves, then serve.