Wash the green beans under cool water. Snap or cut off the stem ends.
Fill a large pot halfway with water and add a pinch of salt. Bring to a boil over high heat. Add the green beans and cook 5–7 minutes until bright green and tender-crisp. Drain.
Heat a skillet over medium heat. Melt the butter until foamy. Add the drained green beans. Sprinkle salt and black pepper over the beans.
Toss beans in butter using tongs or a spoon. Cook 3–4 minutes, stirring often, until beans are shiny and well-coated. Serve immediately.