When the pan is hot, put the oil, stir-fry the beans and add some water. When beans become less bright green, they are ripe. You can try using a spatula to see if they are soft, and then wait until the pot is hot before adding seasoning. When the oil is hot, stir-fry the beans and add some water. When beans become less bright green, they are ripe. You can try using a spatula to see if they are soft, and then add seasoning.