My parents made this Canh Chua recipe so often that we used to ask “what day are we having Canh Chua this week?” It truly was a weekly soup for us and we loved it. Loaded with healthy veggies and fish, it's no wonder my parents made it so often.
Canh Chua is a traditional Vietnamese soup made with a sweet and sour broth. Its direct translation means "sour soup." The addition of a protein, usually catfish, gives you what I am making here, Canh Chua Cá or "Sour Fish Soup." It's also commonly known as Vietnamese Sweet and Sour Soup, Vietnamese Hot and Sour Soup or simply, Vietnamese Catfish Soup. If you choose to use shrimp instead of fish, you have yourself another common variation, Canh Chua Tôm, which is "Sour Shrimp Soup."
The combination of sour, sweet, salty and spicy is commonly found in Southeast Asian recipes. There's a delicate balance between these flavors and Canh Chua is the perfect example. This soup sways toward the sour/tart side with its tamarind soup base and tomatoes. However, it's balanced out with the sweetness of the pineapple, the savoriness of the fish sauce and fried shallots, and spiciness from the Thai chilis. One single taste will keep you wanting more.
If you choose to use fish in this soup, the type of fish you use is entirely up to you. The most traditional types for this dish are catfish or mudfish. My parents always used catfish. We would purchase a whole catfish, use half for Vietnamese Sweet and Sour Fish Soup and use the other half for Vietnamese Caramelized Catfish in Clay Pot (Ca Kho To).
Ingredients for Canh Chua Ca
There are quite a few ingredients in this Canh Chua recipe, some of which are my personal favorite. In fact, they're what make this soup so special. Each ingredient brings a different flavor and texture to the party. Depending on where you live, a few of the ingredients may not be readily available. I offer some alternatives that you can use in a pinch. Don't let the ingredients list intimate you. This is a very quick and easy soup to make.
CATFISH: Have your fishmonger clean and cut the whole catfish into steaks. I prefer thicker cuts, 1.5"-2", but you can go with any thickness you wish. If the skin feels slimy, rub it with some salt, then rinse it off with cold water. Frozen catfish, catfish filets or any mild flaky fish work great as well. Not a fan of fish? A common alternative is shrimp. Whole shrimp, with head and shell on is preferred.
TAMARIND CONCENTRATE: My mom used to make the catfish soup base by soaking tamarind pulp in hot water. It was a time consuming process of soaking, squeezing and straining. I found that using tamarind concentrate worked just as well and it was a real time saver. This is the heart and soul of the soup and unfortunately, there isn’t an alternative to this. You can't make Canh Cua without it. Fortunately, you can buy tamarind concentrate online.
FISH SAUCE: Along with tamarind concentrate, fish sauce is the other main flavoring component. It adds a depth of flavor along with brininess and umami to the soup. Is there such a thing as Vietnamese soup that does not use fish sauce? I have yet to encounter one.
TARO STEMS (BAC HA): Taro stems (bac ha) are often referred to as Elephant Ear for its large leaves. Although it does not add much flavor, it acts (and looks) like a sponge, sucking up soup and adding a delightfully unique texture. To prepare taro stems, peel off the tough outer skin row by row. Cut crosswise into half inch thick slices on a bias to expose more of the spongy texture. This is one of my favorite ingredients of the soup. Substitute with celery stalks if you're unable to find taro stems.
RICE PADDY HERB (NGO OM): Rice paddy herb (ngo om) is another one of my favorite ingredients for this soup. It has a bright, fresh, citrusy flavor to it. Naturally, it's the perfect palate cleanser for a soup loaded with so many different flavors. A rough chop is all you need to do to prepare rice paddy herb. If you can't find it, you can use Thai basil or lemon basil as a substitute.
LEMONGRASS: This adds a bright lemony flavor with hints of ginger and rounds out the soup base. To prepare lemongrass, remove the dry, green outer layers until you have a pale yellow core. Trim and discard the top half of the lemongrass which doesn't have much flavor. All the flavor is in the thick end of the stalk. With the back of a knife or a pestle, carefully pound and bruise the thick ends to release the citrusy flavor. You can skip lemongrass if you can't find it. However, don’t give up too quickly. I've seen lemongrass at most supermarkets, even Walmart.
FRIED SHALLOTS: You can make this yourself or buy it in a jar. It's basically sliced shallots that have been lightly dredged in flour and deep fried. You can find fried shallots in the dried food aisle of most Asian markets. This is an optional topping but like most ingredients here, I recommend it if you have it.
How to Make Mom's Canh Chua Ca Recipe
Conveniently, Vietnamese Sweet and Sour Catfish Soup can be made in one single pot. For this recipe I'm using a 4 quart Dutch oven, but any medium-sized pot or larger will work.
1) Start by heating the pot and a tablespoon of oil over medium heat. Add minced garlic, sliced chilis and lemongrass. Sauté the aromatics for 10-20 seconds to give the garlic some color and release the intense flavors.
2) Add the tamarind concentrate, fish sauce and sugar. Stir well to incorporate and allow it to come to a boil. Since the pot is already hot, the soup base will begin to bubble quickly.
3) Next comes the acidic components. Add tomatoes and pineapple, then top it off with 6 cups of water. Turn the heat to high and bring the soup to a boil. Reduce the heat, cover and simmer for 10 minutes. All the incredible complementary flavors will begin to meld together.
4) After 10 minutes of simmering, add the catfish steaks. Allow it to simmer for another 10 minutes, uncovered. Depending on the thickness of your fish, you may need to add or subtract some time. The 2” steaks pictured above took about 10 minutes to cook through.
5) While the fish is cooking in the soup, occasionally skim off some of the scum and impurities that rise to the surface. I do this halfway through the cooking process, then one more time right before serving.
6) When the fish is fully cooked, add bean sprouts and taro stems then turn off the heat. The bean sprouts and taro stems will continue to cook in the hot soup. Top it off with chopped rice paddy herbs and fried shallots and serve immediately.
I hope you enjoy this Canh Chua Ca recipe. A typical dinner at our house usually included this Vietnamese Sweet and Sour Fish Soup, a bubbling pot of Ca Kho To (Vietnamese Caramelized Catfish in a Clay Pot) and a plate of Bo Luc Lac (Shaking Beef). A perfect trifecta!
- 4-6 catfish steaks
- 3-5 cloves of garlic, minced
- 2 Thai chilis, sliced (optional)
- 2 stalks of lemongrass, with the ends bruised
- 2 tomatoes, cut into wedges
- 1 cup pineapple chunks
- 10 oz bean sprouts
- 2 stalks of taro stems (bac ha), peeled and sliced on a bias
- 5-8 springs of rice paddy herb (ngo om), chopped
- 1 handful of fried shallots
- In a 4 quart or medium-sized pot, heat up a tablespoon of oil over medium heat. Add minced garlic, sliced Thai chilis and lemongrass. Saute for about 10-20 seconds, just until the garlic begins to change color.
- Add tamarind concentrate, fish sauce and sugar to the pot. Mix well and allow it to come to a boil.
- Add 6 cups of water, tomatoes and pineapples. Turn the heat to high and bring to a boil. Lower the heat to medium-low, cover and allow it to simmer for 10 minutes.
- Uncover, turn the heat back to high then add the catfish and bring back to a boil. Reduce the heat and simmer uncovered for another 10 minutes or so, until the fish is tender. Periodically, skim off any scum or impurities.
- Add bean sprouts and taro stem (bac ha), then turn off the heat. The remaining residual heat will cook the taro stems and bean sprouts.
- Serve with a generous topping of fried shallots and chopped paddy herb (ngo om).