If you know the comforting smell of lemon-scented wood soap or furniture polish, you’ll recognize the same fragrance in preserved lemon. It has all the sunny aroma of fresh lemon, but is somehow more deeply complex. Used frequently in South Asian and Indian cuisines, it’s little more than lemons, lemon juice and salt — sometimes with a few spices added to it — left to cure until the lemons have lost all of their bitterness and sourness. The pulpy rind is then used to add a touch of lemony gold to tagines, curries, and soups. Try it anywhere you’d use lemon zest to complement a savoury dish, and you’ll marvel at its flavour.