1. Preheat the oven to 400 degrees.
2. Cut the onions into quarters and gently pull back the papery skin, just enough so the outer onion layers are exposed. Put the onions in a baking dish.
3. Mix the orange juice, 1/3 cup water, coriander and brown sugar together and pour the mixture over the onions, making sure to get between the papery skin and outer onion layer.
4. Cover the baking dish and onions with foil and bake for 40 minutes at 400 degrees or until the onions are soft. Remove the onions from the baking dish and set aside in a serving dish, removing the papery skin as desired.
5. Carefully pour the remaining liquid from the baking dish into a pot over medium heat. Mix the corn starch together with the remaining teaspoon of water. Add the cornstarch mixture to the onion baking liquid and bring it to a boil. Reduce the heat to low, stir until the cornstarch thickens the glaze.
6. Drizzle the thickened glaze over the cooked onions and serve.