Vietnamese Sour Fish Soup with River Leaf (Canh Chua Lá Giang)
If you enjoy Vietnamese home cooking, and you are up for hunting down items that can be a wee bit tricky to find in the U.S., give Canh Chua Lá Giang a try.
- 1 1/2 lbs fish (whole or filet catfish, salmon or any fish of your choice. You can also use chicken thighs cut into bite-size pieces)
- 1 tablespoon fish sauce
- 3 chili peppers (optional; slice thin)
- 2 tablespoons vegetable oil (or other neutral oil)
- 3 garlic cloves (peel and roughly chop)
- 1 small shallot (peel and roughly chop)
- 1 1/2 quarts water (can sub with chicken stock to omit bouillon/seasoning powder)
- 200 grams blanched river leaf (about 10 oz fresh)
- 1 ripe red tomato (slice into thin wedges or cubes)
- 3 tablespoons granulated white sugar
- 1 teaspoon fine ground sea salt
- 2 tablespoons chicken bouillon powder or mushroom seasoning powder
- Peel and finely mince the garlic and shallots. Thinly slice the chilies. Clean the fish then cut into large pieces. Set aside.
- Marinate the fish with fish sauce and chili peppers for at least 30 minutes at room temperature or overnight in the fridge.
- In a medium-size stockpot, heat the vegetable oil over medium-high heat. Add the garlic and shallot and sauté until fragrant.
- Add the marinated fish along with its juices and marinade liquid. Toss the fish with the aromatics for about 3 minutes over medium-low heat. Add the tomatoes and gently toss them with the aromatics as well on the bottom of the pot.
- Add water and river leaf. Simmer the soup over medium-low heat for about 20 minutes. Season with sugar, salt, and bouillon powder/seasoning powder, adding a little at a time to taste.
- Turn off the heat, garnish with cilantro or additional chilies for a beautiful presentation, and serve as a side dish with steamed rice.
This is a classic sweet, savory, and sour Vietnamese soup. It gets its tartness from lá giang (river leaf) rather than the usual tamarind.
The savory stock base is made from either simmering chicken, fish, or other seafood, and the sour leaves are the main vegetables that get balanced with a bit of sugar.
Altogether it creates a comforting and traditional Vietnamese vegetable soup that goes wonderfully with a warm bowl of steamed rice.
What is La Giang?
Lá giang, also known as river leaf, sour-sop creeper, or by its scientific name Aganonerion polymorphum, is a tropical climbing vine native to Southeast Asian countries like Vietnam, Cambodia, Laos, and Thailand.
The leaves on this plant has a very tart flavor that is similar to sorrel (rau chua) but with an even more pronounced sourness. So tart that it will make you pucker up.
La giang is often used as a leafy vegetable in traditional Vietnamese sour soups (Canh Chua). When combined with sugar and chilies in soup, the tartness mellows out to create a savory, spicy, and sour balance.
Where to Get River Leaf (La Giang)
I get mine from my mother-in-law whenever she visits Vietnam. Believe it or not, she brings lá giang home with her, among other questionable items.
To bring it home legally from another country, it must be boiled down, frozen, and sealed with miles of thick packaging tape.
My garage freezer is reluctantly filled with packages of frozen lá giang from Vietnam.
However, if you live in a diverse community with plenty of Asian supermarkets, you might be able to find them fresh in grocery stores, or even already boiled and frozen in the freezer aisle.
Why You Will Love This Recipe
When I have that craving for Canh Chua, I just thaw out my frozen boiled La Giang and I’m ready to go. No other vegetables are necessary unlike other Canh Chua recipes.
For the recipe below, I used lá giang with fish. When made with fish as the stock, it’s called Canh Chua Lá Giang Nấu Cá. And any fish will do. I have used salmon and other buttery fish, such as Golden Pompano (pictured).
If you’re not a fan of fish, you can also use chicken; bone-in chicken thighs cut into bite-sized pieces work very well.
