Slice the fish thinly, but not wafer thin, and put into a bowl.
Add a pinch of salt and squeeze in the lime juice (tip: if you roll and press the lime, you get more juice). The acid of the lime cooks the fish, so you will see it change colour.
Remove the seeds from the pomegranate by bashing the back of each 1/
Lay the fish on a plate, and from a height sprinkle on the lime zest and scatter over the pomegranate seeds. Use a sharp grater, such as a microplane, and grate the ginger over the top. To finish, drizzle over the oil and scatter on some small basil leaves.