Quarter lemons and fill with salt.

Preserved lemons are a unique ingredient often used in North African cuisines. They add a zesty, citrusy note to a dish, as well as a bit of color.

It’s not too hard to find jarred preserved lemons in gourmet stores, but making them at home is even easier. Buy a bunch of lemons, and make two lengthwise cuts into each one, from one end almost to the other, so that each lemon is quartered, but still held together at the stem. Fill the inside of each lemon with salt, and drop into a glass jar such as a Mason jar, with a tight-sealing lid. Press down on the lemons, and add more salt. Squeeze the juice of another set of lemons, and pour the juice into the jar. There should be enough salt and juice to cover the lemons. The acid and salt are the preservatives. The salt will draw water out of the lemon peels and give it a firm texture, and a distinct flavor.

Wait at least a month before using the lemons. Their flavor improves over time, and they will keep for more than a year in the refrigerator. Indeed, some chefs who use preserved lemons wait a whole year to use them, to get the strongest flavor from them.