Lift the tofu out of its liquid, and cut the tofu into 3/4 inch cubes. Place the cubes on paper towels and let drain, about 15 minutes.
Remove the shells from the thousand year-old eggs and roughly chop each egg.
Rinse the preserved mustard greens to remove excess salt, drain, and mince. Place mustard greens in a bowl, along with the chopped egg, cilantro, scallions, sesame oil, rice vinegar and soy sauce. Gently toss to mix the ingredients.
Place the tofu on a platter and top with the chopped relish. Serve immediately.