I used enough cabbage to feed 4 people; about 4-5 cups or so Black mustard seeds may be purchased at Indian grocery stores (rai) Heat oil in wok over medium heat. Add black mustard seeds and cook until they pop. Add ground tumeric. Add some slices of red & white cabbage (about 3 cm wide) about 4 cups in total, stir until oil coats cabbage. Cook until wilted; about 4-6 minutes. Serve immediately.