Instruction

• Twist the heads from the prawns, then peel away the legs and shells, but leave the tails intact
• Devein each prawn
• Fry the shells in 1 tbsp oil for 5 mins, until dark pink and golden in patches
• Add the wine, boil down by two thirds, then pour in the stock
• Strain into a jug, discarding the shells
• Heat the rest of the oil in a deep frying pan or casserole
• Add the fennel, onion and garlic, season, then cover and gently cook for 10 mins until softened
• Meanwhile, peel the potato and cut into 2cm-ish chunks
• Put into a pan of cold water, bring to the boil and cook for 5 mins until almost tender
• Drain in a colander
• Peel a strip of zest from the orange
• Put the zest, star anise, bay and ½ tsp harissa into the pan
• Fry gently, uncovered, for 5-10 mins, until the vegetables are soft, sweet and golden
• Stir in the tomato purée, cook for 2 mins, then add the tomatoes and stock
• Simmer for 10 mins until the sauce thickens slightly
• Season to taste
• The sauce can be made ahead, then reheated later in the day
• Meantime, scrub the mussels or clams and pull away any stringy beards
• Any that are open should be tapped sharply on the worktop – if they don’t close after a few seconds, discard them
• Reheat the sauce if necessary, then stir the potato, chunks of fish and prawns very gently into the stew
• Bring back to the boil, then cover and gently simmer for 3 mins
• Scatter the mussels or clams over the stew, then cover and cook for 2 mins more or until the shells have opened wide
• Discard any that remain closed
• The chunks of fish should flake easily and the prawns should be pink through
• Scatter with the thyme leaves
• To make the quick rouille, stir the rest of the harissa through the mayonnaise
• Serve the stew in bowls, topped with spoonfuls of rouille, which will melt into the sauce and enrich it
• Have some good bread ready, as you’ll definitely want to mop up the juices