Bún Riêu (Vietnamese Crab Noodle Soup)

Bún riêu is a Vietnamese noodle soup made with a savory tomato broth, rice vermicelli noodles, and tender crab-and-pork mixture that cooks right in the soup. It’s one of my favorite Vietnamese noodle soups, especially with fried tofu, fresh herbs, water spinach, and plenty of lime.

This is the quicker version we usually make at home. Instead of simmering pork bones for hours, I start with chicken broth and build the flavor with tomatoes, fish sauce, bouillon, and seasoned shrimp and crab pastes. The soup still has all the parts I love, but it comes together in about 40–45 minutes.

If you’ve never made this soup before, some of the ingredients may be unfamiliar. I’ll walk you through what to look for at the Asian grocery store and how everything comes together.

What Is Bún Riêu?

Bún riêu is a Vietnamese rice noodle soup known for its tomato-based broth and soft, savory crab mixture that cooks directly in the soup. Recipes vary by family and region, but the mixture can include crab, ground pork, shrimp, dried shrimp, and eggs.

The soup is served over thin rice vermicelli noodles with fried tofu and fresh vegetables and herbs. At our house, I especially like it with water spinach, herbs, and a squeeze of fresh lime.

Traditional versions can take much longer to prepare, especially when the broth is made by simmering pork bones or fresh crab. Depending on the family or region, you may also find versions with pork trotters, pork blood, tofu, and other additions.

My version is more practical for making at home. I use chicken broth instead of making a pork bone broth, but the crab-and-pork mixture is still made with ground pork, fresh and dried shrimp, crab meat, eggs, and seasoned seafood pastes.

A Few Ingredients Worth Knowing

You’ll find the complete ingredient list and measurements in the recipe card below, but there are a few ingredients that are especially helpful to know before you start.

Seasoned Shrimp Paste and Crab Paste

You’ll need two different seasoned seafood pastes for this recipe. I use both because they add different layers of seafood flavor to the crab-and-pork mixture.

For the shrimp paste, I use Super Brand Shrimp Paste with Soya Bean Oil, which comes in a jar.

For the crab paste, I use Por Kwan Minced Crab in Spices, which comes in a can.

These are the two products I recommend looking for at an Asian grocery store. They are seasoned pastes packed in oil, and they’re different from the very concentrated fermented shrimp paste you may also see on the shelf.

That distinction is important because the products aren’t interchangeable in the amounts used in this recipe.

Don’t throw away the oil in the containers, either. I save some and use it to sauté the shallots and tomatoes, which adds more flavor and color to the broth.

Crab Meat

I prefer lump crab meat because I like its flavor and texture, but it can be expensive. Canned crab meat works well too and is an easy way to make the soup more affordable.

Whichever you use, drain it well before mixing it with the pork and shrimp.

Ground Pork

I use 80/20 ground pork. The extra fat helps keep the crab-and-pork mixture tender as it cooks in the broth.

Leaner ground pork will work, but I’ve found that the finished pieces can be drier and firmer.

Fresh and Dried Shrimp

This recipe uses both.

Fresh shrimp helps with the texture of the crab-and-pork mixture, while dried shrimp adds a more concentrated seafood flavor.

If you’ve never cooked with dried shrimp, you’ll usually find small bags of them at an Asian grocery store. Soak them in hot water for about 10 minutes to soften them, then drain and finely mince them before adding them to the mixture.

Rice Vermicelli

Look for thin rice vermicelli noodles made for Vietnamese noodle soups.

Cook the noodles separately rather than directly in the soup. This keeps them from becoming too soft and prevents the extra starch from getting into the broth.

If you’re not sure which noodles to buy or how to prepare them, my How to Cook Rice Noodles guide goes into more detail.

Fried Tofu

Fried tofu is one of my favorite parts of this soup, so I don’t treat it as an optional topping. It absorbs some of the tomato broth while still keeping its chewy texture.

You can usually find already-fried tofu in the refrigerated section of an Asian grocery store, or you can fry tofu yourself at home.

Water Spinach

Water spinach, also called ong choy, is a leafy green with long hollow stems that’s commonly served with Vietnamese noodle soups.

For this recipe, it’s one of my favorite vegetables to add along with fresh herbs. If you’re shopping at an Asian grocery store, look for it in the produce section.

Please scroll ⬇️ to the recipe card for the full ingredient amounts and instructions.

How to Make Vietnamese Crab Noodle Soup

There are a few components, but the cooking goes fairly quickly because you can work on several of them at the same time. The easiest way is to start soaking the dried shrimp and heating the water first, then prepare everything else while you wait.

1. Soak the dried shrimp and start the broth.

Place the dried shrimp in a small bowl and cover them with hot water. Let them soak for about 10 minutes.

At the same time, add 4 quarts of water to a large stockpot, cover, and bring it to a boil. You can prepare the crab-and-pork mixture while the water heats.

2. Prepare the crab-and-pork mixture.

Process the fresh shrimp in a food processor until finely ground.

Once the dried shrimp have softened, drain them well and finely mince them in the food processor.

Combine the ground pork, fresh shrimp, dried shrimp, drained crab meat, eggs, seasoned shrimp paste, and seasoned crab paste in a large bowl.

Mix everything until evenly combined.

The mixture will be much softer and wetter than a meatball mixture, so don’t worry if it doesn’t feel firm. It should be moist but still thick enough to mound on a spoon rather than run off.

3. Season the broth.

Once the water is boiling, add the chicken broth, fish sauce, bouillon, and sugar. Stir until the sugar and bouillon dissolve, then reduce the heat to maintain a gentle simmer.

4. Sauté the tomatoes and shallots.

Heat the vegetable oil and some of the reserved oil from the seafood pastes in a skillet over medium heat.

Add the shallots and cook for about 2 minutes, until softened and fragrant.

If you want a deeper red-orange broth, you can add a little paprika at this point.

Add the tomatoes and salt and cook for another 2–3 minutes. You’re not trying to cook the tomatoes down completely. They should begin to soften while still holding their shape.

Transfer everything in the skillet, including the flavorful oil, to the broth.

5. Cook the crab-and-pork mixture.

This is the part where you’ll want to pay the most attention if you’re making the soup for the first time.

Scoop about 1½ tablespoons at a time directly into the gently simmering broth.

Once you’ve added the mixture, don’t stir the soup right away. Give the pieces time to cook and set. They’ll begin floating toward the surface as they cook.

Keep the broth at a gentle simmer rather than a hard boil. Stirring too soon or boiling too aggressively can cause the pieces to fall apart.

Let them simmer for about 10–12 minutes, or until completely cooked through.

6. Cook the noodles and add the tofu.

While the soup simmers, prepare the rice vermicelli according to the package directions. Drain well and set aside.

Add the fried tofu to the soup and simmer for another 2–3 minutes, just until it’s heated through.

Taste the broth before serving. Depending on the brands of broth, bouillon, fish sauce, and seafood pastes you use, you may need a little more fish sauce, salt, or sugar.

7. Assemble the bowls.

Place the cooked rice vermicelli in each bowl, then ladle the hot broth, tomatoes, fried tofu, and plenty of the crab-and-pork mixture over the noodles.

Finish with water spinach, fresh herbs, and a squeeze of lime.

You can also set out bean sprouts, shredded cabbage, Thai basil, mint, purple perilla, green onions, and cilantro and let everyone add what they like.

What to Serve With It

My favorite bowl has fried tofu, water spinach, plenty of fresh herbs, and lime. The tofu absorbs some of the savory tomato broth, while the greens, herbs, and lime add freshness.

You can also serve bean sprouts, shredded cabbage, Thai basil, mint, purple perilla, green onions, and cilantro on the side so everyone can build their bowl the way they like it.

If you see mắm tôm mentioned as a condiment for this soup, that’s concentrated fermented shrimp paste. It has a very strong, salty flavor, so it’s usually served in a small amount on the side rather than added in the same quantity as the seasoned shrimp paste used in the crab-and-pork mixture.

You don’t need every traditional topping to enjoy the soup. When I’m keeping things simple at home, fried tofu, water spinach, herbs, and lime are the ones I reach for.

Bun Rieu Troubleshooting

How to Store and Reheat

Keep the noodles and fresh toppings separate from the soup when storing leftovers. Otherwise, the noodles will continue soaking up the broth and become too soft.

Store the broth with the crab-and-pork pieces, tomatoes, and tofu in an airtight container in the refrigerator for up to 3 days. Reheat it gently on the stovetop until hot rather than bringing it to a hard boil.

Keep the cooked noodles in a separate container, then add the fresh greens, herbs, and lime when you’re ready to eat.

If you’ve wanted to try making bún riêu at home but the traditional long-simmered broth felt intimidating, this is a good place to start. You still get the savory tomato broth, tender crab and pork, fried tofu, noodles, and fresh toppings, but this version is manageable enough to make in about 40–45 minutes.

RECIPE