Holy Basil | Bai Gaprao | กะเพรา

Holy basil is revered in Thai cuisine for its unique aroma and flavor. Although it is not used as extensively as Thai basil is, holy basil's unmistakable taste makes it irreplaceable in the dishes that do call for it. Read on to learn more about this distinctive herb and how it's used in some of Thailand's best dishes.

When my husband and I first started dating, one of his Thai friends would very sweetly bring him a bunch of holy basil whenever she went shopping at her local Thai market. At the time, I didn't have any clue what this strange herb was or what to do with it.  So it just sat on his countertop, wilting away day after day...

Recounting this story now is just painful, and embarrassing.  Now that I know what holy basil is, I'll go to great lengths to find it, including driving an hour plus in heavy traffic to the less-than-pristine neighborhoods where the Thai markets reside.

So what makes this herb so worth seeking out? Its highly distinctive flavor that just can't be substituted with any other type of basil. This unique flavor is the basis of Pad Kra Pao, Pad Kee Mao, Jungle Curry, Po Tak soup, and several other lesser-known Thai dishes. Read on to learn more about this irreplaceable herb and how it's used in Thai cooking.

What is Holy Basil?

Holy basil is a type of basil that is native to the tropical regions of Asia and India. It is now widely cultivated in these regions and can be found all throughout Thailand. The scientific name of holy basil is Ocimum tenuiflorum. This herb was given its holy name because of its sacred status in Hinduism and importance along trade routes. In India, holy basil is known as Tulsi. In Thai, it is known as Gaprao or Kaprao (กะเพรา), although it is often misspelled as Kra Pao in English.

Holy basil is a a small annual or perennial shrub that can grow up to 3 feet tall. It can be distinguished from other types of basil by its hairy stems and somewhat soft and fuzzy leaves with saw-tooth edges. The leaves can be green or purple, depending on the variety. Both varieties are used in Thai cooking, with the purple-leafed variety having a stronger, more concentrated flavor.

What does Holy Basil taste like?

Holy basil has such a unique, distinctive flavor that it's somewhat hard to describe. That said, here's my best attempt: Imagine a cross between Italian basil and mint with a large dash of cloves and a lingering aftertaste of black pepper. As you can see, its flavor profile is very complex.

Holy basil has earned the nickname of "hot basil" due to its fairly intense peppery flavor. When it is eaten raw, it can actually numb your tongue slightly. When eaten in stir fries or soups, it may leave you with a pleasant tingling sensation in your mouth.

How is Holy Basil used in Thai Cuisine?

Holy basil is used in a select number of Thai dishes, mainly spicy stir fries and spicy soups. It is also used in some lesser-known rustic salads from the North of Thailand.

The most famous stir fry is Pad Kra Pao, which translates to "Stir Fried with Holy Basil", a testament to the importance of this herb. You can use any meat or protein you like in this dish. If you use chicken, you have Pad Kra Pao Gai. If you use pork, you have Pad Kra Pao Moo. You can also make Khao Pad Kra Pao, a fried rice version of this holy basil stir fry.

Another spicy stir fried dish that uses holy basil is Pad Kee Mao AKA Drunken Noodles. This spicy and satisfying noodle dish features lots of Thai chilis, fresh veggies, young green peppercorns, and the star of the show: holy basil.

Gang Pa (Jungle Curry) is a water-based curry made with an assortment of fresh vegetables, Thai chilis, young green peppercorns, and holy basil. Po Taek (Shipwreck soup) is a spicy and sour soup similar to Tom Yum, but with the addition of holy basil leaves.

Where can you find Holy Basil?

Holy basil can be challenging to find outside of Thailand. Here in North America, your best bets for finding holy basil are local farmer's markets and stores that cater to the Thai or Southeast Asian populations. I can often find bunches of holy basil in these markets during the summer and early fall months. You do have to examine the bunches carefully, as the leaves of holy basil are quite fragile and will wilt quickly if not stored properly.

Another option for procuring this herb is to grow your own plant. Holy basil seeds are widely available online, or you could start with a holy basil seedling. These plants grow best in warm environments with plenty of sunlight and moisture. They are not frost tolerant, but can be brought inside during the colder winter months.

Keeping it Fresh

If you are lucky enough to be in possession of some holy basil, create a makeshift greenhouse to keep it as fresh as possible. Place the stems in a glass filled with water, making sure to trim off the bottom leaves so that they're not touching the water. Place a clear plastic bag over the holy basil leaves, and secure it to the glass with a rubber band. This will help to hold the moisture in, keeping the holy basil fresh for up to two weeks.

I do not recommend storing holy basil in the refrigerator, as it's a very fragile herb and tends to wilt and turn brown when the temperature is too cold or too hot. Simply leave the makeshift greenhouse on your counter, out of the way of direct sunlight.

If you're fortunate enough, some of the stems might even sprout roots while soaking in the water. I always do a happy dance when I see tiny roots starting to grow! If this happens for you, allow the roots to grow until they're at least 1 inch long, then you can gently pot them in fresh soil and marvel as your rootlets turn into holy basil plants.

Storing it

If you're not able to use all of the fresh holy basil before it's starting to go bad, you can store it in the freezer. Pluck the leaves from the stems, wash them, and dry them very well. Then place the leaves in a single layer in a freezer-safe bag, seal it tightly, and put it in the freezer.

Holy basil leaves will keep in the freezer for many months in this manner. When you're ready to use them, simply break off a section of leaves and add it to your dish. The leaves will turn brown more quickly than if they were fresh, but the taste will still be there!

Substitute for Holy Basil

Because holy basil can be challenging to find, people are always looking for substitutes. Unfortunately there is no good substitute for the unique, distinctive flavor of holy basil.

That said, many of the dishes that holy basil is used in still taste good when you use a different herb, such as Thai basil or Italian basil. Take for instance Pad Kra Pao. If you don't have holy basil on hand, you can follow the same recipe but substitute Thai basil for the holy basil, making Thai Basil Chicken (Pad Horapa) instead. The resulting flavor profile is quite different, but delicious nonetheless.

Dried holy basil leaves and holy basil seasoning pastes are available. I did a Thai Test Kitchen head-to-head comparison with these against fresh holy basil, and spoiler alert: they unfortunately just didn't compare. Here's the full Thai Test Kitchen Holy Basil comparison for all the details.