Travel: Vietnam and sour tamarind soup with prawns

With seafood and a medley of spices, herbs, fruits, and vegetables, canh chua soup celebrates the abundance of Vietnam's Mekong Delta. 

From the Tibetian highlands to the lowlands of southwest Vietnam, the Mekong River and its thousands of tributaries meanders across 39,000 square kilometers (15,000 square miles) in Vietnam known as the Mekong Delta or miền tây (western region), encompassing the lands immediately west of Saigon to the country's southern most tip, Cà Mau.

Known as a biological treasure trove, the Mekong River sustains more than 17 million inhabitants along its banks in Vietnam's delta region. Its waters and rich soil help to produce half of the country's rice crop each year, as well as an abundance of fruits. The delta is also home to a large aquacultural industry raising catfish, shrimp, and basa – a fish native to the delta.

Life here revolves around the river – owning a boat is just as important as a scooter, if not more so, as it means you can ferry your crops to the river market to sell. The Cái Răng market in Cần Thơ, is one of the largest floating markets in the region. Mainly a wholesale market for fruits and vegetables, its daily bustle has become a must-see destination for anyone visiting this area.

Each morning at sunrise, the floating market teems with activity. Hundreds of large wholesale boats from all over the delta converge and drop anchor in the river, hanging their crops on bamboo poles to signal what’s in season and for sale. We’re not sure if there’s any order to it all – with bananas on one end and dragon fruit on the other – but the anchored larger boats create lanes, or market aisles if you will, for smaller retail boats (and tourists boats) to weave through. Instead of aisle numbers and shopping carts, simply look at the produce hanging from a bamboo pole at the end of a boat and navigate over to a vendor to place your order. Soon bundles of fruit and vegetables are tossed into your boat. It’s an extraordinary a way of doing business that you’ll rarely experience.

If you see household items on the boat, such as clothes, pots and pans, or even pets, it doesn’t mean these items are for sale. Some families actually call the boats home!

As with markets on land, there’s no shortage of food options to satisfy all the hungry vendors and visitors. You can flag down floating cafes to indulge your cà phê sua da (Vietnamese iced coffee with milk) morning fix as well as banh mi (baguette sandwiches) boats to satisfy your breakfast cravings.

Oh, but you’ll rather have a bowl of hủ tiếu (noodle soup) instead? No problem! There’s a boat for that, too. If you succeed in eating a bowl of noodles in a bobbing boat, after you are finished, the noodle lady will navigate around back to you and retrieve her bowl and chopsticks. The ingenuity and perseverance of the water vendors is simply amazing.

But the Mekong Delta isn’t known for hủ tiếu or even pho (another noodle soup) for that matter. It’s known for dishes that uses the abundant seafood and vegetables from the region such as hot pots called lẫu mắm made from salted fish as well as one of our favorite soups, canh chua. We adore canh chua because the contrasting flavors of sour, sweet, and savory and we also love the contrasting textures of all the different vegetables. Literally translated as "sour soup," canh chua combines all the wonderful abundance of this region, incorporating seafood (such catfish, snakehead, eel, shrimp among others) along with colorful medley of tamarind, pineapple, tomatoes, okra, elephant ears, bean sprouts, and a variety of herbs such as lemony ngo om. Enjoy canh chua with some steamed jasmine rice as part of a traditional Vietnamese meal or alone with some rice vermicelli noodles.

Every time we make this dish, we’ll always remember the floating fruit vendors and life on the Mekong. If you are planning a trip, hire a small private boat to visit the market early around sunrise, or slightly after, when it is the most busy.

We love using prawns for this dish but you can use your favorite seafood. Any firm white fish steaks would work well.

This recipe requires preparing tamarind pulp. It's best to use wet seedless tamarind typically sold in 14-ounce blocks instead of juice or concentrates, although you certainly could if pressed for time. For why and how to prepare the pulp, see this link by Leela of shesimmers.com.

Canh Chua Sour Tamarind Soup

6 cups of water or fish stock
1/2 pound large prawns, cleaned
1 cup tamarind pulp purée
1/2 sweet pineapple, peeled, sliced into bite-sized pieces
2 tomatoes, cut in wedges
2 tablespoons sugar, plus additional to taste
1 tablespoon kosher salt, plus additonal to taste
1 tablespoon fish sauce
1-2 elephant ear stems, peeled and sliced on diagonal 1/2-inch thick
1 cup okra, sliced diagonal
2 red chilli, sliced (optional)
1/2 cup of bean sprouts
10 springs of rice paddy herb, roughly chopped
fried garlic

Combine the tamarind pulp in equal amounts (i.e., 14-ounce block, 14-fluid-ounces of water, roughly 1 cup) of hot water in a large bowl and soak for 15 minutes. Work the pulp with your hands until dissolved, squeezing out the purée and then tossing away the membranes. You're left with just the thick brown pulp purée. You can also strain the pulp through a fine sieve instead of using your hands.

In large pot bring water or fish stock to boil and then add prawns, tamarind pulp purée, tomatoes, pineapple, okra, fish sauce, salt, and sugar and bring back to boil.

When prawns are pink and tomatoes are just tender, add bean sprouts and elephant ear stems and season with additional salt or fish salt and sugar to taste. It should be sweet, sour, and savory.

Remove from heat and transfer to serving bowl. Finish with rice patty herb, fried garlic and optional chili.