Place the chives in a bowl and pour boiling water over them. Leave for 10 seconds and drain. Set the blanched chives aside.
Heat the oil in a non-stick pan. When oil is hot, add mushroom slices and coat them with the oil. Cook over high heat without stirring until one side of the mushrooms caramelizes. Remove mushroom slices from the pan and set aside.
Stir together rice vinegar, carrot, tomato, and radish. Set aside.
Take one leaf of bok choy and cut off any large part of the stem. Press your finger along the remaining part of the leaf’s rib to relax it. Lay the leaf flat.
In the bottom middle of the leaf, place a tablespoon of fish sauce. Add a few mushroom slices and some of the pickled carrot/radish/tomato mixture. Top with a few cilantro leaves.
Fold in the sides of the leaf over the top of the filling and roll it up away from you. Secure each wrap with a blanched chive.
To make the dipping sauce, combine soy sauce, Chinese black vinegar, water, hot sauce, and scallions in a bowl. Add salt and pepper to taste and serve with the rolls.