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Prahok​​ (ប្រហុក) is a crushed, salted and fermented fish paste (usually of mud fish) that is used in Cambodian cuisine as a seasoning or a condiment[1]. It originated as a way of preserving fish during the longer months when fresh fish was not available in abundant supply. Because of its saltiness and strong flavor, it was used as an addition to many meals in Cambodian cuisine, such as soups. Prahok has a strong and distinct smell, earning the nickname Cambodian Cheese[2]. Prahok is usually eaten with rice in the countryside or poorer regions.

Because it is easily stored and preserved, Prahok is sometimes distributed as a donation to victims of flood or drought by charities and other organizations. It can be eaten cooked or fried, but is usually not eaten raw because of health issues (raw Prahok cannot be stored long due to its going bad if not eaten in a short period of time) and the unpleasant smell it makes.

Although Prahok is a dish invented by Cambodians, there was a similar condiment in ancient Rome called Garum, also made from fermented fish and used as a seasoning. There are also other versions of similar foods such as Pissalat from France.
Prahok is prepared using fresh fish (both large and small). Typically, the larger the fish, the more valuable the Prahok made from it. Some types are rarer than others and the rarest are considered delicacies, thus are more expensive. One of the pricier types is one made from the gourami fish.

Prahok is obtained by crushing or grinding fresh fish after de-scaling, gutting and cleaning them. They can be crushed underfoot, like wine grapes, or processed by machine. After the fish is crushed, it is left in the sun for a full day, then salted and sealed in jars full of salt.

Prahok can be eaten after just 20 days of fermentation, but better quality Prahok can be preserved for one to three years.
Types of Prahok:
Fried Prahok
Prahok jien ​ (ប្រហុកចៀន) It is usually mixed with meat (usually beef or pork) and chilli. It can also be eaten as a dip, accompanied by vegetables like cucumbers or eggplants, and rice.
Covered Prahok

Prahok gop or Prahok ang (ប្រហុកកប់) or (ប្រហុកអាំង) This type of prahok is covered with banana leaves and left to cook under a fire under pieces of rock or over the coals.
Raw Prahok

Prahok chao (ប្រហុកឆៅ) This type of prahok can be used to make a paste with lemon grass, lime juice, fresh peppers, and​ Thai eggplant eaten with steak. Also this is the type of Prahok preferably used as a dipping paste for vegetables and fruits .