Ingredients for Crab Soup
Mud crabs: 500g; Tomatoes: 3, Tofu: 2 pieces, Water spinach, basella alba or jute: 300g, 1 fragrant gourd, spring onions, and coriander: 50g, crab fat: extracted from mud crabs, tamarind or sour fruit: 1-2 pieces. Spices: salt, pepper, sugar, fish sauce, cooking oil. Shallots: 2 bulbs.
Tips for Choosing Delicious Crabs
To select tasty mud crabs, opt for those that are still alive and actively crawling. Ensure they have all their limbs, especially their legs. Choose crabs with a brownish-yellow shell and a plump body; those with larger claws are fresher.
Avoid picking very small crabs that crawl sluggishly or have broken claws or missing legs, as they may have been stored for a long time and might not have much meat.
Tips for Cleaning Crabs
Here are the steps to clean the mud crabs before cooking the soup:
Step 1: Soak the crabs in a container of clean water or rice-washed water for about 30 minutes to allow them to expel any mud and impurities.
Step 2: Fill another container with water and gently scoop the crabs into it. Use chopsticks to stir the water in a clockwise direction about 5-10 times. This will cause the crabs to clamp onto each other, preventing them from pinching your fingers when you separate their shells.
Step 3: Detach the shells and aprons of the crabs, then use a toothpick, spoon, or fork to carefully extract the crab fat into a separate bowl.
Step 4: Process the crab bodies by either blending them in a food processor or pounding them in a mortar.
Step 5: Mix the processed crab meat with filtered water in a 2:1 ratio, then slowly strain the mixture through a fine sieve or clean cloth to obtain the crab broth, discarding the solid remnants.
How to Cook Delicious Crab Soup with Floating Crab Fat
First, prepare your choice of greens: water spinach, jute mallow, or basella alba. Clean and separate the leaves, discarding the old stems. Rinse them thoroughly several times to remove any dirt or sand, then set them aside to drain. Peel the fragrant gourd, wash it with diluted salt water to remove the resin, and cut it into diagonal slices.
Cut the tofu into small cubes. If you prefer a more flavorful and intact tofu, lightly pan-fry each side—a handy trick to prevent the tofu from disintegrating during cooking.
Wash the tomatoes and cut them into wedges to add sweetness and a vibrant color to the soup.
Finely chop the spring onions and coriander, adding a delightful aroma to the dish.
Tamarind or sour fruit is essential to imparting a refreshing sour taste. For ripe tamarind, soak it in hot water for a few minutes to soften, then mash and strain the pulp for the juice. Alternatively, for fresh sour fruit, simply scrape off the skin, wash it thoroughly, and add the whole fruit to the crab broth.
Place the crab broth over medium heat on the stove, without stirring, allowing the crab fat to gradually coagulate and float to the surface in golden clumps. Once the fat has set, gently scoop it out with a ladle, being careful not to break it apart.
Sauté the shallots in a little cooking oil or lard to enhance the soup’s fragrance. Gently cook the crab fat with a pinch of salt and pepper to firm it up without melting. When the fat turns a golden orange, add the tomato wedges, cooking them until soft, then lightly mash them to release their juices and lend a vibrant hue to the broth.
Combine the crab fat and tomato mixture with the crab broth. Now, add the tamarind or sour fruit juice that you prepared earlier.
Season with salt, fish sauce, and a touch of sugar (adjust to your taste), stirring to incorporate.
Add the tofu and gourd first. Once the broth comes to a boil, introduce the drained greens of your choice—water spinach, jute, or basella alba—cooking them for about 2-3 minutes until tender. Finally, return the scooped-out crab fat to the soup, sprinkle in the chopped spring onions and coriander, give it a gentle stir, and turn off the heat.
Ladle the crab soup into a large bowl and sprinkle with pepper to enhance the flavor. Serve this hearty soup hot with steamed rice, accompanied by dishes like fish stew or boiled meat dipped in shrimp paste—a quintessential Northern Vietnamese feast.
