Kdam Chaa Mrech Kchei.

Kep and Kampot sit side by side on Cambodia's southern coast, and between them they supply both halves of this dish. The Kep crab market is a row of shacks built over the water where women wade out to wicker baskets of live crab kept submerged offshore; the pepper comes from trellised vines a short drive inland in Kampot province. Pepper has been grown there for centuries and became a French colonial export prized in Paris kitchens by the early twentieth century. The plantations were destroyed during the Khmer Rouge years, when farmers were forced into rice production and the vines were left to die, and the crop was rebuilt from a few surviving farms during the 1990s. Kampot pepper now holds a protected geographical indication, the first Cambodian product to do so.

Green peppercorns are simply unripe berries picked on the stem and used immediately, before they are dried into black pepper or ripened into red. Fresh, they are wet, mildly hot and intensely aromatic, and they behave like a vegetable rather than a spice — Cambodians and Thais both cook with them by the handful. This is why the dish cannot be honestly recreated with black pepper: swapping in ground pepper produces a peppery crab, but not this dish, where you are eating the pepper as much as the shellfish.

At the Kep shacks the crab goes from basket to wok in minutes, still fighting, and the whole thing arrives at the table in a metal dish with a baguette and a saucer of lime and pepper. Nobody attempts elegance. You crack shells with your hands, suck the sauce out of the legs, mop the wok juices with bread, and strip the peppercorn stems bare. Frozen green peppercorns from an Asian grocer, or brined ones rinsed well, get a home version surprisingly close.