Barbecued Pork Ribs

• 2–3lb (0.9–1.4 kg) pork ribs
• salt

Place the ribs in a single layer in a roasting tin. Sprinkle with salt and cook in an oven heated to 400°F (200°C) or gas no. 6 for about 30 minutes.

Meanwhile, prepare the barbecue sauce. Peel and finely chop the onion. Heat the oil in a saucepan over low heat, add the onion and fry gently for about 5 minutes to soften but not brown. Combine the tomato ketchup, vinegar, brown sugar, mu