Heat the oven to 200C/180C fan/ gas 6. Toss the squash and turnips in a roasting tin with half the oil and seasoning. Roast for 20-25 mins, until soft and charred at the edges.

Heat the remaining oil in a large pan over a medium heat. Season and fry the leeks for a few minutes, until softened slightly. Add the squash, turnips, garlic and vinegar, and cook for about 2 mins until sticky. Stir in the capers, olives, raisins and tomatoes, fill the can with water, swill it around and add that, too. Reduce for 15-20 mins, partially covered with the lid, until the veg is tender. Stir in most of the basil and season. Scatter over the rest of the basil and serve with crusty bread.