To make the mustard pickle, crush all the spices together. Put them in a pan with the remaining ingredients. Bring to a boil and leave to cool. Keep until needed.
Place the egg, egg yolks, mustard, kaffir lime leaves and lime juice in a food processor. With the motor running, drizzle in the oil until the mixture thickens. Add the zest to taste and season.
Fry the scallops in the canola oil until nicely browned on each side and slightly opaque in the middle. Do not to overcook them.
Using a mandolin or very sharp knife, slice the cucumber into thin strips. Salt the cucumber in a colander and set to one side for a few minutes to drain off excess water
Arrange the cooked scallops on a plate, and toss the croutons over.
Dot around the plate with some of the lime mayonnaise. Drape the cucumber slices over the top along with a couple to teaspoons of the mustard pickle and garnish well with the baby lettuce leaves.
