Cá kho is a traditional dish from Vũ Đại, Hà Nam that has become famous worldwide. Cá kho is cooked using a clay pot and firewood, which gives the fish a firm texture and a delicious aroma. Despite its high price compared to the market, Vũ Đại’s cá kho is still favored by many people. You can easily recreate the village’s cooking technique using an electric rice cooker or a clay pot on a gas stove…

Ingredients:
800 – 900 gr of black carp fish. Black carp fish has firmer and more fragrant meat than white carp fish.
200 gr of pork belly, choose a good and even cut with a combination of fat and lean meat.
45 ml of fermented crab paste (cua đồng ủ chua) (fermented crab paste is made by salting and fermenting crabs and then extracting the liquid).
Flavoring: Galangal, ginger, dried shallots, and chili.
Seasoning: Fermented shrimp paste, salt, sugar, soy sauce, monosodium glutamate, pepper, and lime.
Clay pot and firewood (optional).
Step 1: Preparation:
When you buy the black carp, remember to remove the scales, gut, and clean the black membrane inside the belly. Then rub the fish with salt and lime and rinse it thoroughly. This is the secret to effectively remove the fishy smell of the people in Vũ Đại village. To make the fish more firm, you can sprinkle a little salt on the fish. This will help the fish become firm and enhance the taste.

Fermented crab paste is what gives the unique flavor of Vũ Đại’s cá kho. After cleaning the crabs, crush them with your hands and strain the liquid. Mix the liquid with salt, thính ngô, crushed galangal, and shallot peels. Stir well and store in a sealed jar to ferment next to the firewood stove. After about 7 days, the crab paste will have a fragrant aroma.
For the galangal, choose fresh ones with skin, slice them thinly. The skin of the galangal gives a distinct aroma, so don’t remove it. The galangal skin also has many health benefits.
The fish sauce should be made from fermented fish, not industrial fish sauce, to make the dish more delicious.
Lime juice is essential when cooking cá kho. It helps the fishbone dissolve quickly, prevents it from being fishy, and makes the bone softer and the meat firmer. Some people may use vinegar instead of lime juice, but lime juice is better.
Brown the sugar until it turns amber, do not burn it.
Step 2: Marinating:
After rubbing the fish with salt, marinate it with crushed galangal, dried shallots, 3 tablespoons of fermented crab paste (45ml), 2 tablespoons of delicious fish sauce, 2 – 3 tablespoons of broth, 2 tablespoons of lime juice, 2 tablespoons of sugar, 1 teaspoon of salt, 1 teaspoon of pepper, and 1/2 teaspoon of monosodium glutamate or seasoning powder.
After adding the seasonings, use your hands to knead the fish until it absorbs the marinade evenly. Marinate for at least 30 minutes, or if you have time, marinate for about 2 hours.

Step 3: Simmering:
In Vũ Đại village, a clay pot from Nghệ An province or a pot imported from Thanh Hóa province is used for cooking cá kho. This is why there is a saying that goes ”Nồi Nghệ An, vung Thanh Hóa, cá Đại Hoàng” (Nghệ An pot, Thanh Hóa stove, Đại Hoàng fish).
A clay pot is a traditional cooking utensil that enhances the flavor of the dish because it regulates heat evenly, unlike metal pots. Moreover, the clay pot does not react with the ingredients.
You can place a layer of galangal slices at the bottom of the pot, then place the fish on top, followed by the pork belly. Pour the marinade into the pot. Cooking cá kho Vũ Đại is quite complicated as it takes up to 12 hours for the fish to become tender, flavorful, and edible including the bones.
Alternatively, you can cook it in 2 stages: First, bring the pot of fish to a boil for about 3 – 4 minutes to allow the fish to absorb all the flavors (the marinade prevents it from burning). Then pour enough boiling water into the pot to cover the surface of the fish. Reduce the heat and simmer gently, season the dish again to ensure the taste is perfect. After 40 – 45 minutes, turn off the heat and let it cool. This helps the fish become tender and the meat firmer. Second stage of cooking: Before serving, simmer the pot of cá kho over low heat, add the pork belly at this time. Occasionally shake or use a ladle to evenly coat the fish with the broth. Note that when the broth is almost gone, leaving only 1/3 of the broth, add more boiling water to continue cooking. The total cooking time for cá kho is about 2 – 3 hours.
The finished cá kho from Vũ Đại village has fragrant and firm meat, edible bones, and a distinct aroma of galangal and fermented crab paste.
It may be difficult for you to cook cá kho with the traditional method at home, but you can use an electric rice cooker and learn the techniques of the village. Remember to wash the fish with salt and lime to remove the fishy smell, and add lime juice to make the dish more tender and fragrant.