If you want to make chili garlic tofu with some gravy, after adding the sauces, add 1.5-2 cups of water and let it boil. In a bowl mix ¼ cup of water at room temperature with 1.5 tablespoons of cornstarch and add to the boiling sauce. Stir continuously and cook until the sauce thickens. Add baked tofu cubes and cook for another minute.