Cut the tofu into 4 slabs, then cut each of those slabs in half. Place the pieces into a pan with a little oil over medium-high heat. (There is no need to press the water put of the tofu.) Cover the pan with a lid and allow to saute for 10-12 minutes. It will sputter and pop, which is fine.
While the tofu is browning, make your sauce by combining the next 8 ingredients. Heat over low heat in a small saucepan.
Check on your tofu. If it is well browned, flip the pieces over and continue to brown the other side. Be careful when removing the lid , which will collect steam over cook time and drip into the pan, causing sputtering. Allow to brown for an additional 10 minutes or so.
Once the tofu is done, increase the heat for the sauce to medium. Once it starts to slightly boil, pour in the cornstarch/water slurry and whisk for a minute or two until slightly thickened. Remove from the heat.
Pour the sauce over the browned tofu and sprinkle with sesame seeds. Serve immediately.