From its rolling hills in the east to the fertile plains of the west and the pristine coastline of its southern flank, Cambodia’s topography is as varied as its cuisine. Regional specialties highlight locally available ingredients, and recipes have been passed down from generation to generation.

Hailing from the agricultural heartland of Cambodia’s northwestern provinces is m’chu kroeung pong ang krong, a spicy sour soup made with red ant eggs. But not just any ant will do. The original recipe calls for the eggs of a particular species of tree-dwelling ant.

The soup is prepared by boiling the ant eggs in a meat stock, and packed with flavour by adding a medley of crushed herbs and spices that include aromatic kantraub leaves, lemongrass, turmeric, galangal, garlic and kaffir lime leaves – as well as a dollop of prahok (fermented fish paste).

“The people in my village usually only prepare this soup for ceremonies and special occasions during the harvest season or Khmer New Year,” says Ly Saluy, a resident of Phnom Srok district in Banteay Meanchey province. “It requires elaborate preparation and can be very difficult to cook.”

Cambodian cuisine is largely centred on fish, though beef makes an occasional appearance as the star of national dishes such as lok lak (stir-fried beef salad with rice) and plea sach ko (spicy beef salad). In the rustic northeastern province of Ratanakkiri the local indigenous Khmer and Lao tribes tend to use more red meat in their cooking – though fish still manages to find its way into most recipes.

One local specialty is maphea, a hearty dish made from the meat and innards of young cows, and cooked with prahok and wild vegetables.

“Maphea is very popular here and the signature dish of the province,” says Nget Vitou, head of the province’s tourism department.

Chut Chhengleang, owner of Punlea Pich restaurant near Banlung, explains that maphea is prepared using the cow’s internal organs – its stomach, kidneys, bladder and small intestines – which are boiled then thinly sliced. Prahok and vegetables are mixed in and the pungent stew is allowed simmer in a pot, then given a measure of cow bile for some bitter kick.

“People in the countryside say the hint of bitterness is what makes maphea especially delicious,” says Chhengleang.

A regional specialty in Steung Treng province, where life revolves around the mighty Mekong River, is trey paseh-y dot, made from a bottom-feeding river fish known in Khmer as paseh-y.

Retired chef Tha Vy says the dish is usually prepared when the fattened paseh-y move downriver after spawning.

“To prepare paseh-y, we slit the fish’s stomach and remove all the organs then clean it out with water,” she explains.

“After that we pack it thick with banana leaves or the outer husk of a banana tree and grill it on hot coals until it’s fully cooked.”

Most chefs will add salt, fish sauce, sugar, roasted peanuts, red garlic, ripe chillies, lemon juice and some shredded carrots. But like many Cambodian recipes, it is all up to the individual chef.

“You just mix the ingredients together until you achieve the taste you desire,” Vy says.