This aromatic, heart-shaped leaf can be so much more than a decorative garnish for sushi.
Shiso, the aromatic heart-shaped leaf with a saw-toothed edge, is probably most familiar to Americans as a sushi garnish. But this relative of mint and basil, available at farmers’ markets and Asian groceries, is employed in a number of Asian cuisines for more than its attractive appearance. Botanically known as Perilla frutescens var. crispa, it is often tucked into Vietnamese summer rolls or shredded and added to cold noodle salads.
The two common varieties of shiso are green and reddish-purple in color. We found the former to have a minty, bitter, lemony flavor with a faintly sweet finish. The latter variety is milder in flavor, though some tasters found it extremely bitter (the purple color is due to a compound called anthocyanin to which some people are more sensitive than others; it is thought to be the cause of the leaf’s bitter taste). Both the red and green leaves are slightly astringent.
In addition to its traditional uses, we liked shiso tossed into salads as we would herbs such as mint or basil. However, larger leaves can be tough, so make sure to tear or shred them first. Shiso can also be used in cooked applications, such as fried rice or ramen, or fried whole and used as a garnish. Even a small amount of heat will cause the leaves to brown slightly, but their flavor will be preserved as long as you add them toward the end of cooking.