Make the Chilli Vinegar in advance. Bring the vinegar and sugar to the boil in a saucepan and simmer until the sugar dissolves. Pour this into a vinegar dispenser along with the dried chillies and allow to cool. This can be kept in the fridge indefinitely.

Put a splash of water in a large saucepan and bring to the boil. Add the cockles, cover the pan and cook for about 5 mins until the cockles have opened. Drain through a colander and, when cool enough to handle, remove the meats from the shells. Put the meats in a bowl, pour in sufficient milk to submerge them, then cover the bowl with cling film and put in the fridge for at least 2 hours.

When ready to cook, drain the cockle meats from the milk and keep aside.

Combine the two flours and the polenta in a large bowl. Mix well.

Heat sufficient oil in a saucepan or wok to 180°C. Take a first batch of cockle meats (only as many as will not overcrowd the pan) and dredge them in the flour and polenta mix. Shake off the excess coating then transfer them into the hot oil and deep-fry for about 5 mins until they have crisped up and are golden in color. It is important not to overcrowd the pan as they will not crisp and may clump together. Remove this first batch to a plate lined with kitchen paper, sprinkle with some of the chopped chilli and some sea salt flakes and keep warm.

Repeat with the next batch until all the cockles are cooked then serve with the chilli vinegar.