Asam Laksa (Spicy and Sour Noodle Soup) Recipe

Do you even want fish noodle soup if it's not spicy, sour, and savory?

Overhead view of Asam Laska S

Serious Eats / Michelle Yip

Why It Works

  • The use of small fish increases the ratio of bone to meat, which makes the soup stock deeply flavorful.
  • Boiling the Vietnamese mint and torch ginger flower buds in the stock and then adding them fresh as a garnish creates a balanced flavor and richly herbal and floral aroma.

Usually, when people hear the word “laksa,” they imagine a big bowl of noodles topped with a thick, coconutty curry soup. While curry laksa is indeed one of the more well-known dishes from Southeast Asia, there’s actually a whole wealth of laksas to discover. In Malaysia, “laksa” essentially means “noodle soup,” as there isn’t really anything that ties the different kinds of laksas together other than them all being noodles in soup. The variety of laksas from state to state is almost staggering, from the spice-rich prawn-based gravy and thin rice noodles of Sarawak laksa to the fish-based Johor laksa served with spaghetti (yes!), to the soft rolled rice noodles in creamy fish gravy of Kelantanese laksam. The laksa I'm writing about here though, is my personal favorite and probably the most aromatic of them all, the Penang asam laksa.

Side view of Asam Laska

Serious Eats / Michelle Yip

Penang, an island off the west coast of Malaysia has some of the best street food this side of the globe, and is deservedly world-famous as a destination for gastronomes. One of its most famous dishes is asam laksa, a strongly spicy, sour (“asam” means “sour”), and savory fish soup served with thick rice noodles and various aromatic herbs. The use of small, oily fish such as chub mackerel or sardines is necessary for the making of the stock: Their high ratio of bone to meat means that the flavor of the stock will be much stronger, providing the depth necessary to highlight the bright herbs that are cooked in the stock and served raw as garnish.

Overhead view of cleaning the fish

Serious Eats / Michelle Yip

I’ve tried experimenting with larger oily fish like tuna and Spanish mackerel, but the stock just did not have enough punch. Deboning the fish can be a bit of a pain even for me, but I roll up my sleeves and get on with it while catching up with podcasts, and before I know it, I’ve deboned a whole kilo's worth. If you’re considering white fish, don’t, as it doesn’t have the fatty mouthfeel necessary for the soup stock, and the flesh disintegrates too easily when boiled in soup. Garnish-wise, it’s almost like a who’s who of Southeast Asian flavors. From different kinds of mint to thin chunks of pineapple, each bowl can (and should) be customized to the preference of the eater. If you don’t feel like hunting down every single aromatic item, make sure you at least have torch ginger flowers and Vietnamese mint—asam laksa simply won’t taste or smell the same without them. More easily available vegetables like julienned cucumbers and shredded lettuce will do just fine to add a fresh crunch to the dish.

Overhead view of torch ginger flowers and Vietnamese mint

Serious Eats / Michelle Yip

Because of their labor-intensive prep, laksas are usually eaten outside the home during office lunch breaks or weekend brunches with the family. When they’re made at home, especially with recipes like asam laksa that use small fish, it’s very much for a special occasion. This particular recipe is heavily based on a recipe by one of my favorite fellow Malaysian cooks, Dinesh Rao, one of the owners of beloved (though now-closed) restaurant Tray Cafe in Kuala Lumpur, which in turn is based on his own tinkering with his mother’s recipe and others he’s come across. It comes pretty darn close to what you can find at hawker stalls—deeply, pleasantly fishy, with a heady aroma of fresh herbs that you’ll dream about for days. Make the trip to your local Asian grocery stores for the ingredients; I promise you it is well worth it.

Side view of lifting noodles

Serious Eats / Michelle Yip

Recipe Details

Asam Laksa (Spicy and Sour Noodle Soup) Recipe

Prep 10 mins
Cook 2 hrs
Total 2 hrs 10 mins
Serves 6

Ingredients

For the Soup:

  • 2 pounds (1kg) chub mackerel, sardines, or other small, oily fish, gutted and cleaned (keep the heads on)

  • 10 1/2 cups (2.5L) water

  • 1 pound (450g) dried thick rice noodles, or 21 ounces (600g) fresh thick rice noodles (see notes)

  • 10 Asian shallots (about 5 ounces; 150g), peeled and sliced

  • 12 dried Kashmiri chiles, stemmed and sliced, soaked in hot water

  • 2 fresh medium-hot red chiles, such as fresnos, stemmed and sliced

  • 2 torch ginger flower buds (about 3 1/2 ounces/100g; see notes)

  • 4 stalks lemongrass, pale bulbous bottom part only, outer leaves discarded, tender core thinly sliced (about 1 1/2 ounces; 40g)

  • 1/2 ounce (15g) fresh or frozen galangal, peeled and thinly sliced

  • 2 tablespoons (30g) shrimp paste, preferably Malaysian-style belacan

  • 5g fresh turmeric, peeled and thinly sliced (see notes)

  • 2 medium garlic cloves, peeled and smashed

  • 2 tablespoons (30ml) tamarind concentrate

  • 4 pieces asam gelugur or kokum (optional; see notes)

  • About 1 cup (50g) Vietnamese mint leaves (see notes)

  • 2 1/2 tablespoons granulated sugar, plus more as needed

  • 1 tablespoon kosher salt, plus more as needed

  • Neutral oil, such as vegetable or canola oil, as needed for noodles

For Serving: (all garnish are optional)

  • Picked fresh spearmint mint leaves

  • Pineapple, sliced into thin chunks (preferably fresh)

  • 3 to 5 Asian Shallots, peeled and thinly sliced

  • Fresh chiles, such as fresnos, stemmed and thinly sliced

  • Torch ginger flower buds, thinly sliced (see notes)

  • 3 calamansi oranges or Persian limes, halved

  • Petis udang, thinned with hot water to make about 1/2 cup of a thick, pourable consistency (see notes)

Directions

  1. For the Soup: In a medium stock pot, bring the water to a boil over high heat. Add fish and cook for 5 minutes. Remove from heat. Using wire skimmer, transfer fish to a bowl and let cool for 10 minutes. Using a measuring cup, measure out 2 cups fish stock and set aside; leave remaining stock in pot. Debone fish, reserving heads and bones separate from fish meat. 

    Four image collage of cooking fish and then separating broth and cleaning fillets

    Serious Eats / Michelle Yip

  2. In a food processor, combine fish heads and bones with 1 cup reserved stock. Process until it becomes a thick slurry, about 1 minute. Stir slurry back into stock, bring to a boil over medium-high heat, and cook, adjusting heat as needed to maintain simmer, for 30 minutes.

    Overhead view of spooning processed fish into broth

    Serious Eats / Michelle Yip

  3. If using dried rice noodles, soak them in hot water and set aside while preparing spice paste and soup.

    Overhead view of noodles soaking in water

    Serious Eats / Michelle Yip

  4. While fish stock is cooking, in a clean food processor, add shallots, soaked dried chiles, red chiles, torch ginger flower buds, lemongrass, galangal, fresh turmeric, garlic, shrimp paste, and remaining 1 cup measured fish stock. Process, scraping down sides as necessary, until the mixture becomes a smooth paste, about 1 minute.

    Two image collage of ingredients in the food processor bowl before and after being processed

    Serious Eats / Michelle Yip

  5. Strain fish-bone stock through a fine-mesh strainer into a large non-reactive bowl; discard crushed fish bones. Rinse stock pot clean, then pour strained stock back into pot. Add processed spice paste along with tamarind concentrate, asam gelugur (if using), Vietnamese mint leaves, and deboned fish meat. Stir. Bring to a simmer over medium heat and simmer, stirring occasionally, until broth is slightly viscous and intensely flavored, for 1 hour. Stir in 2 1/2 tablespoons sugar and 1 tablespoon kosher salt then adjust seasoning to taste.

    Two image collage of adding chili paste and fish into soup and bringing to a boil

    Serious Eats / Michelle Yip

  6. While broth is cooking, finish preparing the rice noodles. If using dried rice noodles: Drain soaked noodles, place in a large saucepan, add water to cover by about 1 inch, then bring to boil over high heat. Cook until the noodles are cooked through, about 20 minutes. Immediately plunge into ice water to stop the cooking process, then drain again. Toss with 1 teaspoon neutral oil to prevent the noodles from clumping and set aside. If using fresh rice noodles: Blanch in boiling water for about 30 seconds, then drain. Toss with 1 teaspoon neutral oil to prevent the noodles from clumping and set aside.

    Overhead view of cooked noodles in a bowl

    Serious Eats / Michelle Yip

  7. For Serving: Divide noodles among serving bowls. Pour 2 to 3 ladles of soup straight over noodles, making sure to include chunks of fish. Garnish each serving with any combination of spearmint leaves, pineapple, shallots, chiles, and torch ginger flower buds. Squeeze half a calamansi lime and drizzle 1 tablespoon of petis udang over each bowl. Serve.

    Four image collage of assembling bowls of asam laska

    Serious Eats / Michelle Yip

Special Equipment

Food processor, fine-mesh strainer

Notes

Torch ginger flower buds are available at Southeast Asian grocery stores under the names “bunga kantan” or “kecombrang,” and usually still on the stem. Choose buds that are bright pink and firm. Remove the thick stem from right underneath the bud before using. If you can't find torch ginger flower buds, you can use additional galangal in its place in the stock and omit it as a garnish.

Fresh turmeric can be found in South Asian and Southeast Asian grocery stores. It gives an almost medicinal scent when fresh, and keeps well in the freezer for up to 3 months. If unavailable, omit entirely (do not use dried turmeric powder).

Asam gelugur is the dried slices of the Garcinia atroviridis fruit, native to Peninsular Malaysia. This is available in Southeast Asian grocery stores, also under the name “asam keping.” If asam gelugur is unavailable, substitute with the same amount of kokum (a fruit distantly related to asam gelugur, available at South Asian grocers), or 1 more tablespoon of tamarind concentrate.

Vietnamese mint is available at Southeast Asian grocery stores, and is also (confusingly) called “Vietnamese coriander,” “Cambodian mint,” “phak phai,” or “laksa leaf.” It wilts relatively quickly on the counter, so put it in the fridge as soon as you get it home from the market.

Rice noodles are available dried or fresh in East Asian and Southeast Asian grocery stores. Look for a high percentage of rice flour (at least 80 percent) with no wheat fillers. 

Petis udang is available at Southeast Asian grocery stores or online. It’s also referred to as “shrimp paste” but is not the same thing as belacan or Filipino patis; petis udang is much sweeter in flavor, darker in color, and almost molasses-like in texture.

Make-Ahead and Storage

Store the prepared noodles and fish soup in airtight containers in the fridge for no longer than 1 week.

Nutrition Facts (per serving)
622 Calories
13g Fat
102g Carbs
32g Protein
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Nutrition Facts
Servings: 6
Amount per serving
Calories 622
% Daily Value*
Total Fat 13g 17%
Saturated Fat 2g 9%
Cholesterol 148mg 49%
Sodium 1609mg 70%
Total Carbohydrate 102g 37%
Dietary Fiber 12g 42%
Total Sugars 53g
Protein 32g
Vitamin C 250mg 1,252%
Calcium 520mg 40%
Iron 8mg 44%
Potassium 1389mg 30%
*The % Daily Value (DV) tells you how much a nutrient in a food serving contributes to a daily diet. 2,000 calories a day is used for general nutrition advice.
(Nutrition information is calculated using an ingredient database and should be considered an estimate.)