Wrap the block of tofu in a clean kitchen towel or paper towel, and place a weight on top, like a heavy book or a skillet, to remove excess moisture. Press for at least 20 to 30 minutes.
Toss the tofu cubes in cornstarch. Heat sesame oil in a frying pan over medium-high flame; cook them for about 2 minutes on each side until golden brown. Reserve.
In a mixing bowl, thoroughly combine all the sauce ingredients.
Add the sauce to the pan and let it cook over medium heat for about 5 minutes, whisking continuously.
Lastly, add the tofu to the pan, and toss everything together until well coated.
Sprinkle with sesame seeds and serve over rice noodles, if desired. Enjoy!