Put the shrimp in a colander and sprinkle with the salt. Toss with your hands, rubbing gently to make sure all surfaces are evenly covered. Let sit for 5 minutes; then rinse in cold water and drain. Cut each shrimp in half lengthwise and then in half again crosswise.Put the shrimp in a medium bowl and add the shallots, fish sauce, pepper, and sugar. Mix well and let marinate covered at room temperature for 1 hour.

​Put the rice in a spice mill (clean coffee grinder) and pulse it a few times to grind about 10 seconds total. The largest grains will be a third of their original size.

​Heat the oil over medium-low in a 4-quart pot and add the shrimp mixture. Saute, stirring frequently, for 3 to 5 minutes, until all the shrimp are pink and the shallots have softened but not colored. Add the rice and stir well. Gradually add 2 quarts water, stirring constantly to avoid clumping. Raise the heat to medium-low and simmer, stirring often,for 20 to 25 minutes, until the rice is completely tender and the broth has thickened. Raise the heat to high, add the peas, and cook for 3 to 4 minutes, until the peas are just tender; remove from the heat. Add the cilantro, scallions, and pea greens, and season with a splash of fish sauceto taste.

Serve hot.