These small, fragrant citrus fruit are characterised by their knobbly dark-green skins and uniquely double-shaped glossy leaves. The juice and flesh of the kaffir lime are quite bitter, so itβs only the zest and leaves that are used in cooking, finely grated or shredded and added to Asian-style soups, curries and salads, to give them a wonderful tangy flavour. Kaffir limes and leaves are sold in Asian food stores. If unavailable, use lime zest and young lime leaves. Kaffir limes are also known as makrut limes.