Wash the zucchini and pat them dry; cut the ends off and slice them lengthways as thinly as possible – use a mandolin slicer or a potato peeler. Put the slices in a bowl and season them with the mint (setting aside 3 or 4 leaves), salt, the peppercorns squashed with the flat of a knife, the juice and grated zest of the ½ lemon, and the olive oil. Mix, cover with cling film and leave in the fridge to marinate for at least 3 hours. When this time is up, take the zucchini out of the fridge, carefully strain them in case they have produced a little water, leave for 10-15 minutes at room temperature and then serve with the flakes of pecorino and the mint leaves you set aside.