Rinse rice with cold water and drain well in a sieve.
In a medium, heavy-bottomed pot with a tight-fitting lid, combine 1¾ cups water, rice, Matcha, and butter and salt if desired. Bring to a boil over high heat. As soon as the water is boiling, lower the heat to a simmer and cover.
Cook at a gentle simmer until the water is completely absorbed and the rice is tender, about 12 minutes (it's okay to lift the lid to make sure the rice is fully cooked and the water is absorbed-just replace the lid quickly).
Remove the pot from heat and let sit undisturbed with the lid on, for at least 5 minutes and for as long as 30 minutes. Remove lid, fluff the rice gently and serve.