Asian grocers' freezers, often as makrut lime leaves.
1Frozen kaffir lime leaf
The same number
You lose almost nothing — they freeze better than they dry.
2Dried kaffir lime leaf
Simmered in a curry or soup
Twice as many
You lose much of the floral lift; they're also tough, so fish them out.
3Lime zest
A strip of zest, no pith, for every two leaves
You lose the leaf's perfume — zest is just citrus.
Gets some back a little extra lemongrass.