Place 1 1/2 cups white jasmine rice in a large saucepan. Add enough cold water to cover. Swish the grains around with your hands. Pour through a fine-mesh strainer. Return the rice to the saucepan and repeat adding cold water, swishing, and straining.
Return the rice to the saucepan. Add 1 (about 13-ounce) can unsweetened coconut milk, 1 cup water, and 1/2 teaspoon kosher salt, and stir to combine. Bring to a boil over medium-high heat, stirring occasionally. Reduce the heat to low. Cover and cook until the liquid is absorbed and the rice is tender, about 15 minutes.
Turn off the heat. Let the rice sit, covered, for 5 minutes to steam. Uncover and fluff with a fork.