Basil world There are so many types of basil - and they all taste very different. Mint also comes in many varieties but while they vary in intensity and have subtle nuances, they all taste minty. With basil, though, the types used in Mediterranean countries taste very different from those used in Thai cuisine; many varieties have an anise-y flavour, but they can also have notes of cloves, cinnamon or citrus.
Unfortunately, most types of basil aren't available in Hong Kong.
Mediterranean basil (also called Italian basil) has tender, wide, glossy leaves and is used across much of Europe. It's one of the essential ingredients in caprese salad - the red (tomatoes), white (mozzarella) and green (basil) are the colours of the Italian flag. If you see a recipe for basil pesto and it doesn't specify the type, use Mediterranean basil. Of course, you can use other types of basil to make pesto, but the result will be different. Pesto also contains garlic, olive oil and nuts (usually pine nuts), and is made either with a mortar and pestle (the traditional way), or, in a blender or food processor.
In Hong Kong supermarkets, Mediterranean basil is sold in small packs and is expensive. Some vegetable vendors who specialise in lettuce and herbs sell it in large bunches, and much more cheaply.
Thai basil has slender leaves (often on purple stems, although they can be green) that are quite sturdy and strongly flavoured. Mediterranean basil loses much of its flavour when cooked, but Thai basil keeps its distinctive, spicy, licorice-y taste even when simmered in a sauce or used in stir-fries. It can also be eaten raw, or added to soups or other dishes at the last minute, so the leaves just wilt in the heat. Thai basil is one of several types of herbs served with many dishes in Vietnam, including pho and banh xeo (turmeric-flavoured crepes folded over vegetables, meat and shrimp).