This is the tastiest recipe for cooking king prawns in a wood-fired oven. Marinate your prawns in homemade piri piri sauce for least 2 hours before cooking, so that the flavours really sink in. For best results, cook the prawns in a cast iron pan, regularly basting them while they sizzle beside hot embers. Serve with a crisp salad, toasted sourdough bread and a very cold glass of white wine and you have the perfect dinner party starter.