In a mixing bowl, dissolve the caster sugar in 150 ml just-boiled water with 2 tsp of sea salt.

Stir in the rice-wine vinegar and carrot matchsticks and set aside while you crack on with the rest.

Peel the cucumber into ribbons using a vegetable peeler, and pick half the coriander into small sprigs.

Halve the spring onions into green and white lengths, then shred the whites into thin matchsticks.

Toss the cucumber ribbons, picked coriander sprigs and spring onion whites together and leave to one side.

Roughly chop the remaining coriander, the green parts of the spring onion and garlic clove, and put in a food processor with a third of the sliced green chilli.

Blitz until finely chopped, then add the fish sauce, squeeze in the juice of half the lime, and the chopped firm fish.

Season with salt and white pepper and blitz for a minute until smooth.

Add the crab meat, egg and cornflour and pulse until it all comes together.

Halve the baguettes lengthways, and lay out on a chopping board.

Scoop out a little of the bready centre and save for another use, then spread the inside of each baguette with a tablespoon of mayonnaise.

Squeeze the remaining lime half over the cucumber mixture and season.

Drain the carrots.

Put a large frying pan on a medium heat and drizzle in enough vegetable oil to just cover the base.

Shape the crab mixture into small cakes - you are looking for 3-4 per baguette.

Fry half the crab cakes for three to four minutes on each side, until golden and cooked through.

As soon as they're ready, distribute them between two of the baguettes, top each one with a quarter of the herby cucumber mixture and a quarter of the pickled carrots and drizzle with sriracha.

Close the baguette and serve.

Repeat this process with the remaining crab cakes and accompaniments, and tuck in.