Now that it's summer (finally!), it's time to talk about basil.
The Greek name for basil (ocimum) which is where the scientific name comes from "to smell" — clearly the principal virtue of this herb.
The English word "basil" also comes from the Greek and it means "monarch" — entirely appropriate for this "king of herbs".
1. Sweet Basil (Ocimum basilicum = O. basilicum)
This is the traditional variety used in Italian cooking. It's mild and most known for its characteristic aroma. This is what you need to make pesto.
2. Thai Basil (O. basilicum var. thyrisflorum)
It's a variant of sweet basil and it's called bai horapa in Thai. This is the predominant type used in Thai cooking.
This has a strong peppery taste and at least chez CC this is frequently preferred even in Italian dishes that call for black pepper. It has a muscular taste that goes particularly well with pasta dishes that contain vegetables. It's too aggressive for pesto however. For that, you will need to stick with sweet basil.
It's also more heat stable under the classic stir-fry methods of Thai cooking under which sweet basil discolors rapidly. Carefully washed and wrapped in paper towels in a bag, it lasts a lot longer in the fridge as well with its smell intact.
3. Holy Basil (O. sanctum, O. tenuiflorum)
It's called bai kaprao and it's also used in Thai cooking.
It has a strong aggressive anise-like flavor which is a variant to the above. Also used in stir-fries that need a strong taste.
One of the stranger things that the CC notes is that even though this variety is completely widespread in India and even "worshipped", it doesn't make its way into any dish. Devout Hindus will eat one leaf daily and even plant it but it doesn't get eaten. "Basil chutney" rocks the world with samosas and the like and the CC offers up this idea gratis to enterprising Indian chefs.
Followers of politics might be amused that one of the "biggest" controversies in Thailand in 2013 was the banning of the dish pad kaprao (stir-fry with holy basil) in army canteens because of the aggressive flavor spreading throughout. Entirely rational journalists asked why the ventilation fans were not up to the task and a parallel was drawn to the coup. The army commander-in-chief had to personally make a statement that he too loved pad kaprao and he had nothing to do with the ban.
Moral: Men will wage war and put up with military coups but never mess with their beloved foods. That way lies defeat.