Soak the mushroom in water (hot, warm, or cold, depending on how much time you have) to rehydrate. Meanwhile, thaw the frozen tofu at room temperature.

Trim the mushroom of the stems, then finely chop. Transfer to a bowl. Stand over a sink and squeeze on the tofu to expel most of the excess water – until it resembles a moist sponge. Crumble the tofu into the mushroom bowl; don’t make it too small because you want some texture. Add the dark soy sauce and stir well to combine. Set aside.

Cut the tofu into ½-inch (1.25 cm) cubes and put into a bowl. Add enough just-boiled water to cover, then soak for 15 minutes.  Meanwhile, measure out 1 ⅓ cups of water (the stuff you just boiled is fine) and set aside near the stove for later use.

In a large wok or skillet, toast the peppercorn over medium heat for 2 to 3 minutes, until fragrant and slightly darkened. Cool briefly, then pound with a mortar and pestle or grind in a spice grinder. Set aside.

Drain the tofu in a strainer or colander and set near the stove with the other ingredients.

Heat the oil in the wok or skillet over high heat. Add the crumbled tofu and mushroom, and cook for 1 minute until glossy and aromatic. Add the ginger, and chile bean sauce. Cook for about 2 minutes, stirring constantly, until the ingredients are reddish-brown color. Add the sugar and regular soy sauce, stir to combine, then add the tofu.

Gently stir or give the wok a shake to combine. Pour in the 1 ⅓ cups water you set aside earlier. Bring to a vigorous simmer, and cook for about 3 minutes to allow the tofu to absorb the flavors of the sauce.

Taste the sauce and add a pinch of sugar, if needed. Add the green onion, stir, then add enough of the cornstarch slurry to thicken. Sprinkle in the ground peppercorn, restir to incorporate, then transfer to a shallow bowl. Let rest for 5 minutes to meld flavors before enjoying with lots of hot rice.