Meet Bun Rieu’s sister, Canh Bun, which also originated in Northern Vietnam. During the short time I lived in Saigon, Canh Bun was my breakfast of choice. It is called “canh” because you cook the noodles and vegetables in the broth the same way we use the term Banh Canh. Canh Bun is a tad lighter than Bun Rieu, but made in a similar way with smashed rice field crab (cua dong). The usual suspect we find in Canh Bun are tofu, blanched morning glory, and pork blood. All the ingredients are cooked in the broth with the noodles, which add their own flavors to the broth.
It may appear similar to Bun Rieu but definitely have some difference. The crab mixture in Bun Rieu is sturdy and becomes almost like a cake. Canh Bun’s crab mixture is fluffy and easy to break apart. To achieve that fluffy texture fresh rice field crabs are smashed, shell and all, into a paste. The paste is use to flavor the broth, the cooked crab paste then floats to the top of the pot similar to bun rieu. I use frozen ground rice field crab to flavor the broth, no Canh Bun is complete without the aroma and bits of rice field crabs in every bowl. I use a jar of crab meat in soya bean oil instead of the jar we use to make bun rieu, there is less seasoning because it’s just crab meat in oil. Some canh bun vendor does not use tomato, I like tomatoes in mine so it’s your call.
I also included rice paper (banh trang) in the ingredient list. I’m not sure if vendors still sell Canh Bun with rice paper nowaday but it’s a must for me. Rice paper was used as another form of noodle. Since rice paper is cheap, vendor would add it to Canh Bun to make it more filling. I personally love it because the rice paper absorb all the flavor and the texture is just amazing.
pork bones (1 lbs)
1/2 cup of dried prawns (tom kho)
1 container of frozen rice field crab paste
1 jar of crab meat in soya bean oil
shrimp paste (mam tom)
3-4 large tomatoes (quarterd)
1 large bunch of morning glory
pork blood (cubed)
large rice noodle (use for Bun Bo Hue)
herbs of choice (optional)
rice paper (optional)
1. Par boil pork bones. Rinse bones well under cool water. Transfer clean bone to a 6 quart pot and fill with water.
2. Let bone simmer in pot.
3. Soak dried prawns in warm water until soften, and add dried shrimp to the pot.
4. Season the broth with 4 tablespoon of salt, 1 chunk of rock sugar, and 2 tablespoon mushroom seasoning.
5. Sauteed the crab meat in soya bean oil in a smal sauce pan and then add it to the pot.
6. Combine the ground rice field crab with 2 eggs, and blend them together in a blender.
7. Pour the crab mixture into a microwave safe container. Wrap the container with plastic wrap and cook this crab mixture for 10-15 in the microwave. Let the crab mixture cool. There might be excess liquid in the crab mixture, drain as much of it as you can add it to the pot. Set the crab mixture aside for later.
8. Wash morning glory and then blanch, drained and let dry.
9. Cook the noodle until al dente, drained and then let dry.
11. Transfer 1 cup of the broth to a sauce pan, add 2 tablespoon of shrimp paste and let it cook. Once the shrimp paste dissolved completely, add the shrimp paste liquid into the pot. This will help flavor the broth.
12. Add tomatoes, tofu and blood cubes.
13. Add more sugar, and fish sauce if needed.
14. The broth is ready for eating.You can put noodle and morning glory right into the pot and start cooking it. I like to use a separate smaller pot to prepare each bowl. Cook a little bit of everything in the broth. Since the crab mixture is very delicate, keep it on the side until the very end when you are about to transfer the soup to the bowl. Since it is already cooked, I just scoop a little bit of it into the bowl. Enjoy!