Used heavily by the Vietnamese and Laotians as well, Thai Basil (Horapha, โหระพา) is the sweet, slightly licorice-tasting basil that is used to perfume and flavor everything from curries and soups to salads and stir-frys. Purple stems and dark green leaves are the telltale sign that you’re looking at Thai Basil.
The anise flavor, and leaves so sweet you can eat them raw off the stem, is the flavor that will tell you your shopkeeper is selling the real deal. On the other hand, Holy Basil (Bai Gaprow, กะเพรา) is sometimes referred to as hot- basil or pepper-basil – and does not have the same inherent sweetness.
Recipes using Thai basil:
The flavor profile is comprised of an essence of pepper and clove, which intensifies as it is cooked.
Fish sauce and garlic (and bird chilis, of course) work well with the transcendent herbaceousness of Holy Basil – so you’ll see it used in drunken noodles and Pad Gaprow.
Ask a Thai person what their ultimate favorite basil is and 9 out of 10 times, they’ll say Bai Gaprow. And – oh yeah – it truly is considered a holy herb, thought capable of doing all sorts of good things for your body beyond just tasting great.