1/4 cup balsamic vinegar
1 teaspoon dried oregano
2 tablespoons packed brown sugar (or less, to taste)
Salt and pepper, to taste
1/3 cup seasoned bread crumbs
Peel onions and cut a small slice from the top, leaving the root end whole. Cut each onion from the top into 8 wedges, taking care not to cut through the root end. Brush four sheets of aluminum foil with the olive oil.
Mix the remaining ingredients (except for the bread crumbs) and rub the mixture into each of the onions. Wrap each onion securely in its own foil wrapper. Bake at 350 degrees F for one hour or until tender. During the last 5 minutes of baking, open the foil and sprinkle with the bread crumbs.