Combine the rice and 6 cups of cold water in a pot. Sprinkle in the salt and bring to a boil over medium-high heat. When the liquid comes to a boil, reduce the heat to low and cover. Cook the rice for 20 minutes, without peaking under the lid, the steam is most precious in cooking rice. When the rice has absorbed the water it will form “craters” or holes in the top.
Let the rice sit off the heat, undisturbed with the lid on, for at least 5 minutes. This allows the rice to steam, with the bottom layer as fluffy as the top.
Fluff the rice with a fork and transfer to a serving bowl. Add the blanched peas, green onions, lemon juice and zest, mint, and oil; season with salt and pepper. Toss gently, taking care not to smash the grains of rice. Garnish with pea tendrils before serving, if using.