This is an easy process (another lacto-fermented pickle) and a good way to preserve your bounty if you have a lemon tree or to extend your lemon-eating period if you eat seasonally.
Re ingredients, at its simplest, you just need lemons (in Morocco a specific kind is used, but any kind will do), salt and a sterilized jar. In this video, Jules also adds green bay leaves for color and a bit of flavor.
She ferments them for several weeks and says that the preserved lemons will keep in the cupboard, sealed, for about one year. Once open, she stores the jars in the fridge.
Tara shows you what the finished product looks like (she adds spices to her lemons in the jar) and tells you how to use the preserved lemons (you discard the preserved pulp and use the rind cut up finely to flavor dishes) and what they go well with. She says the unopened jars will keep “practically forever, really.”