Preserved lemons, sold loose in the markets of Northern Africa and are an important ingredient of Moroccan cooking--used in a variety of tagines, stews and other dishes. Because of their one-of-a-kind texture and flavor, fresh lemon or lime juice don't make reliable substitutions. Regular lemons from the grocery work just fine and Meyer lemons add a special fruitiness to the finished pickle, so use them if you happen to find them. For the best success, make sure the lemons are completely covered with the salted lemon juice, and to prevent spoilage, only use a clean spoon or fork to remove them from the jar. Don't let the amount of salt throw you too much, the pickles are rinsed off well before being used. The pickling liquid also makes an interesting addition to dressings, sauces, or Bloody Marys. Also check out my recipe for Preserved Lemon Cheesecake.