1. Slice tofu into 6 even cutlets about 1/2" thick. Place on paper towel to drain. Heat nonstick pan. Add 1 tablespoon oil to pan, and add onions when oil is hot. Sauté onions until golden brown and caramelized (about 5-10 minutes).
2. Remove onions, set aside. Add other tablespoon of oil to pan, and add tofu. Fry until golden brown on both sides (about 10 minutes). Add onions back to pan with balsamic vinegar and Worcestershire sauce, and stir.
3. Mix water and cornstarch, and add to pan. Stir until thick. Add water to thin. Add salt and pepper to taste. Plate up this dish with the onions and sauce smothered over the tofu steaks. Serve with a side of roasted asparagus and a nice rice pilaf.