Remove the coarse stalks and central rib from all of the collard leaves and cut them cross-wise into very fine ribbons.
Put the oil in a large, wide pot and set over medium-high heat. When hot, add the onions. Cook, stirring frequently, until the onions are a medium brown color, about 8 minutes.
Add the ginger. Stir and cook 1 minute.
Add the greens, mixing well to thoroughly coat with the hot oil. Add a little water to keep it from sticking.
Cover, turn the heat down to medium-low and cook for 5 – 10 minutes, or until the greens are very tender. Season with salt to taste.