Freeze tofu overnight. Let thaw. Drain and squeeze out any moisture in tofu, dry, and cut into 1 inch chunks. Mix the egg replacer as specified on the box and add an additional 3 tablespoons of water. Toss tofu with egg replacer mixture to coat completely. Sprinkle approximately 3/4 cup cornstarch over tofu and coat completely. Make sure the cornstarch does not form clumps on tofu.
Heat oil in pan and fry tofu pieces until golden. Drain oil.
Heat 3 tablespoons vegetable oil in pan on medium heat along with red pepper flakes (red pepper flakes are optional). Add peppers, white onion, and ginger. Cook for 2 minutes. Add garlic and green onions. Continue to cook for another two minutes. Be careful not to burn garlic. Add vegetable stock, soy sauce, sugar, and vinegar. Return fried tofu to the pan. Mix 2 tablespoons of water with 1 tablespoon cornstarch and pour into mixture stirring constantly until the desired consistency is reached.
Serve immediately with steamed broccoli over your choice of rice.