Slice the lemons as if to quarter them but don’t cut all the way through – leave them connected at the base. Cover the cut inside surfaces liberally with salt and press them tightly into a large jar (or several smaller ones). Add extra lemon juice to cover the lemons – the lemon juice and salt create a brine. Cover the lemons tightly and set aside in a cool dark place – a cupboard or pantry is fine. Leave them to pickle for about four or five weeks, longer if you like. Their flavour will continue to change over time. If you want to preserve a particular flavour, simply transfer the lemons to the refrigerator. Properly preserved lemons will last for years – even at room temperature.
Rinse the lemons before using to remove excess salt and any film that may have formed in the liquid. Use the rind, finely chopped, in salads or in couscous. In tagines, stews and sauces, remove the seeds and use the quarters, with or without flesh. Leaving the flesh will impart a stronger lemon flavour.