Preheat oven to 400°F.
1. Put the onions into a pan, just cover with cold water, cover, and boil for 2-3 minutes. Then drain off the water. Return the onions to the pan, add milk and 4 tablespoons water. Cover and simmer until the onions are tender 10 to 15 minutes.
2. Mix cornstarch to a smooth paste with a little extra milk, add to the onions and stir until boiling. Add 2 tablespoons of the margarine, salt, pepper, nutmeg, and cinnamon.
3. Remove the crusts from the bread, and fry in the oil until brown on both sides. Arrange the fried bread in the bottom and around the sides of a baking dish. Pour in the onion mixture.
4. Sprinkle with cheese and bread crumbs mixed together. Melt the remaining tablespoon of margarine and dribble over the top. Bake until well browned.