Place oil in skillet and sauté chicken cubes until nearly cooked through. Add ginger root slices, scallions, mushroom, soy sauce, cider vinegar and water. Let simmer for 40 minutes up to 1 ½ hours. Optionally, you can put all ingredients into a crock pot on low for 6 hours. The more the stew cooks, the more the flavors meld.