The stone crab or thunder crab is a small crab species with big and hard claws. It lives in rock crevices, wood boards along coastal cliffs and mangroves, as well as in calm shells, aquaculture farms… It is very slow, and can cling to rocks very firmly with its bigs claws. The stone crab is prized only for their claws, because the crab body contains very little meat or flesh.
In Vietnam, this crab species is distributed on the coasts of Quảng Ninh and Khánh Hòa provinces, but more popular in Quảng Ninh where it is called cù kỳ. Other local names in Vietnam include: cua đá (stone crab). There are actually two stone crab species in Vietnam: Myomenippe hardwickii and Menippe rumphii. Myomenippe hardwickii is black, while Menippe rumphii is maroon.
The stone crab is also often mistaken with the red egg crab (Atergatis integerrimus, Vietnamese: cù kỳ đỏ) or the red-streaked box crab/ shame-faced box crab (Calappa lophos, Vietnamese: núm, cúm núm) which is also found in Vietnam.
The stone crab can be cooked in crab noodle soup, steamed/roasted crabs, pan-roasted with tamarind, stir-tossed with glass noodle, or can be made into crab meat floss for children.
This stone crab noodle soup utilizes both the claw meat and the crab body. The crab body are ground to make the broth, along with the tomalley in the crab shell. The noodle used in this noodle soup is bún, Vietnamese soft rice vermicelli. Bún noodle can also be replaced with bánh đa, a Vietnamese broad flat noodle (not to be confused with thick round noodle).
In Quảng Ninh, stone crab noodle soup is often sold together with mantis noodle soup. Often, they mix stone crab, mantis shrimp, and tiger shrimp in a noodle bowl.
Steam the stone crab claws and mantis shrimps with some ginger. Remove the meat from the crab claws and mantis shrimps. Use a small spoon to scoop out the tomalley inside each crab shells. Set aside.
In a kitchen blender, ground the mantis shrimps heads and shells together with the stone crab bodies with with 600 ml water. Use a sieve to strain.
In a pot, sautee some minced shallots and stir fry the tomato wedges for about 5 mins. Add the strained stone crab water/juice and the crab tomalley with 3 TB fish sauce, 1 TB granule seasoning, 1 TB sugar, and cook for about 15 mins. Re-season to taste and turn off the heat.
In a serving bowl, add fried tofu, mantis shrimps fillets, stone crab meat, some chopped greens and herbs, chopped spring onion leaves and sawtooth coriander leaves, fried onion flakes. Pour the hot broth onto the bowl.
Mantis shrimps help making the broth sweeter.
Vietnamese cuisine is the method of cooking, the principle of mixing spices and the general dining habits of all Vietnamese people in Vietnam. With a unique geography, climate, and cultural exchange, the cuisine of Vietnam is extremely diverse and rich. The characteristics of Vietnamese cuisine is the focus on the freshness, so Vietnamese dishes are generally perceived as delicious and healthy.
