There is nothing so wondrous as a kaffir lime leaf.
These deep, glossy, emerald-green leaves impart a heavenly aroma: it’s a scent of rich citrus, as if already infused with coconut and spice. The addition of kaffir lime leaves can make or break an Asian dish, especially Thai cuisine, and the zest of kaffir limes (which look like odd, nubbly versions of regular limes) is an integral part of many curry pastes.
Is there a substitute for kaffir lime leaf? Maybe, but I can’t imagine anything that would add the same delicious impact.
There are numerous ways to add kaffir lime leaf to a dish – you can bruise it, you can tear it, you can add it whole. Or, you can slice it finely. Here’s how I learned to do that in Bangkok.
Take the leaves (most kaffir limes leaves are in double sections) and fold them over so you can grasp the spine, as pictured above; remove the spine. Stack the leaves on top of one another, shiny side up. Roll into a tiny scroll, and then slice finely.
Add a number of kaffir lime leaves, sliced in this manner, to a dish, or use as a garnish. I was surprised in Thai cooking class how many kaffir lime leaves we used — perhaps more than six to a dish. So in doubt, add a few more … and enjoy the result.