Put meat in deep heavy kettle. Cover with water. Boil water and immediately turn down to simmer meat and 1 onion for 3 to 4 hours. Add potatoes for last 45 minutes. Add carrots and turnips the last 30 minutes. Add pearl onions and cabbage the last 15 minutes.
Meat should be removed about 20 minutes before the cabbage is added.
Corned beef is best sliced thin and is often better cooked the day before, cooled in liquid and reheated in same liquid and fresh cooked vegetables. Serves 6.