You may have come across this edible herb at your nursery. A creeping groundcover, it grows prolifically in my garden. Native to Southern Asia from Iran all the way out to Melanesia and Northern Australia, pennywort can grow anywhere where it gets sufficient water, particularly in ditches. It's also known as gotukolle or gota kola (its Sri Lankan name).
I can't comment on how much of that is true, but there is surely something to it. And given how easily it grows, it makes sense to grow some. But here's the rub - it doesn't taste all that great. It's not horrible, but it is somewhat bitter and astringent, and not something you'd naturally wish to munch on.
Yet cook it in the right way and it can be delicious. The key is to balance its bitter taste with salty, sour and/or sweet flavour components. Numerous South and Southeast Asian cuisines make use of pennywort in such ways. Here are a few.
The Sinhalese cuisine of Sri Lanka makes great use of pennywort, in a vegetable preparation called mallung or mallum. There's a recipe for it here, which comes from Charmaine Solomon's classic The Complete Asian Cookbook. You can use any green leafy vegetable for mallung, or a combination of them, but pennywort is a common choice. It's simple and delicious as an accompaniment to rice and curry.
In Vietnam, where it is known as rau ma, pennywort is blended into a drink with water and sugar. You may have seen this green liquid in Vietnamese cafes and grocers. It has a taste which is slightly odd but not unpleasant.
The Kachin people of Burma make an unusual salad from pennywort which I came across on SBS's My Family Feast program. They combine the leaves with sliced tomatoes and red onions, coriander leaves and chilies, while the dressing comes from a combination of lime juice and salty fermented bean paste (easily found in Asian groceries). You can get a recipe and watch it being made here.
The way I most often eat pennywort is in a salad that comes from the Indonesian province of Aceh. It is called sambai on peuga-ga in Acehnese. I've adapted it from this recipe (written in Indonesian) via the Indonesia Eats blog. The leaf is little used in the rest of Indonesia - where it is known as pegagan - except in herbal concoctions. My recipe is a bit rough with measurements, so use your own taste as a guide.
ACEHNESE PENNYWORT SALAD
- 1/3 cup grated coconut (fresh is best)
- a bunch of pennywort, finely chopped
- several lime leaves, finely sliced
- 1/2 stalk finely chopped lemongrass
- 1 clove garlic, finely chopped
- 1 shallot, finely chopped
- juice from 1 lime
- 1 or 2 fresh chilies, finely chopped
- 1/4 cup roasted or fried peanuts, chopped
- a few fried shallots to garnish
- salt to taste
If the coconut is dried, moisten it slightly with a little warm water. Add to all the other ingredients and mix. Serve as an accompaniment to rice and main dishes.
NOTE: There is other plants often known as pennywort (genus Hydrocotyle), which look similar and some of which are edible, but I don't think they have any of the health-giving properties of Centella asiatica. Hydrocotyle leaves tend to be round, while Centella asiatica's are kidney-shaped.