Preheat the oven to 190°C, 375°F, gas mark 5. Boil the potatoes until tender, and squeeze the pips from the tomatoes. Stick a large frying pan on a high heat and sear the lamb until golden. Remove and put to one side while you crush the drained potatoes in the frying pan (use a masher, rolling pin or the likes) then leave to fry for a couple of minutes. Stir the tomatoes and olives into the potatoes with some seasoning and rosemary sprigs, drizzle with a little olive oil and place in a roasting tin. Place the lamb on top of the potatoes and cook according to pack instructions until medium. Slice the lamb into chops and serve with the crispy potatoes and a little salsa verde, or an extra drizzle of olive oil.