Place the salt cod in a bowl and cover with cold water. Cover bowl with plastic wrap and soak for 24 hours, changing the water several times. Drain the fish and dry well, then remove the skin and bones and discard. Place the flesh in a large saucepan, cover with water, bring to the boil and gently simmer, covered, for about 20 minutes. Drain and set aside.

Steam the potatoes until just cooked.

Combine the milk and 1 tbsp of the olive oil in a small saucepan and heat until warm.

In a heavy-based saucepan, heat the remaining olive oil over low heat, fry the garlic and onions for 1-2 minutes, add the salt cod, and stir well with a wooden spoon to break up the flesh.

Put the potatoes through a Mouli grater or ricer and add to the pan, beating well to make a paste. Gradually beat in the warm milk/oil mixture, then add the egg yolk, and pepper to taste. Remove from the heat, cool and chill. Check the seasoning and adjust if necessary.

Roll level tablespoons of the mixture into balls. In small batches, dust with flour, coat with egg mixture, then coat with panko crumbs and shake away any excess. Deep-fry the salt cod fritters in hot vegetable oil for about 1 minute, or until golden and crisp. Drain on absorbent paper.

Drizzle with a squeeze of lemon and serve immediately.