For the chilli salt, toast the sea salt, chilli flakes and peppercorns in a pan for 5 minutes, tossing often. Blend in a small food processor or coffee grinder.
For the aÃ¯oli, whizz the egg yolks, rice vinegar, sugar and 1 tsp salt in a blender. Slowly drizzle in the grapeseed oil until the mixture thickens and emulsifies.
Score the inside of the squid with a sharp knife and cut into bite-sized pieces. Fill a pan a third full with oil and heat. Test the heat by dropping in a small piece of bread - if it sizzlesnd floats to the top, the oil is hot enough. Toss the squid in flour and deep-fry, in batches, for 30 seconds. Drain on kitchen paper and sprinkle over a pinch of the chilli salt.
To serve, put some chilli squid in each lettuce leaf and serve with a lime wedge, some aÃ¯oli and a slice of ciabatta.