Here's what you can substitute for kaffir lime leaves

Kaffir lime leaves are an essential part of Thai cuisine, as well as other Southeast Asian dishes. The leaves have a strong aroma and can be purchased fresh, frozen, and dried. Unlike regular limes, kaffir limes and their leaves are used mainly in cooking and should not be eaten raw (via The Spruce Eats). Kaffir lime leaves have a strong citrus flavor, and they can be difficult to find outside of specialty Asian markets. For those that find the flavor too strong or don't have access to Asian markets, there are substitutes that can be used to attain a similar flavor.

Something to watch out for is the way recipes refer to kaffir lime leaves. "Kaffir" is a derogatory term in Arabic that was previously used by white South Africans, or Afrikaaners, to denigrate black South Africans (via Culinary Lore). As a result, they will sometimes be referred to in recipes simply as 'K-Leaves' or 'makrut.' They may also be called lime leaves or wild lime leaves, though it's important to note that they are different than western lime leaves. The context of the recipe can help to distinguish which limes are required, as Thai or other East Asian recipes that call for lime leaves are likely referring to kaffir lime leaves.

Kaffir lime leaf alternatives

To substitute for kaffir lime leaves, bay leaves are one of the best options (via Raw Spice Bar). They have a similar flavor to kaffir lime leaves, although they do lack the citrus aspect. They work best as a substitute for seasoning soups, sauces, and rice dishes, but definitely don't eat the bay leaf itself — just use it for seasoning, then discard before serving. They can also be combined with lime zest for spicier dishes such as curries.

One of the easiest substitutes is lemon and lime zest. The zest from these fruits offers the same strong citrus flavor needed for certain recipes. Since all that's needed is a lemon, a lime, and a grater, this is a great option. The zest can be used in most recipes instead of kaffir lime leaves.

Lemon thyme can be used in a variety of recipes in place of kaffir lime leaves, in dishes including fish, meat, soup, and salads. Lemon thyme works very well because it has a strong citrusy lemon scent, but without the bitterness of regular thyme.

Another option is lime juice, though it is more limited in its application. Lime juice is a good substitute in Thai curry paste (via Greedy Gourmet).

Any of these options can give dishes the right flavor so they are just as delicious as if they had actually contained kaffir lime leaves.