Add 1 teaspoon kosher salt and the green beans. Bring to a boil and cook, uncovered, until just tender and green beans turn bright green color. Cooking time will vary between 2-5 minutes.
Fill a large bowl of ice water. Submerge the green beans in the ice bath and allow to sit for 5 minutes, then drain in the colander. Season with the remaining 1 teaspoon of salt and olive oil or butter.