wilting mustard greens?

I harvested all my mustard greens the other day, like several pounds of them, brought them in, pulled the leafy bits off the tough stems, washed them, drained them, and set about wilting them in this curious way. Uh, I wanted to make some Vietnamese pickled mustard, but uh, well, did I really think this would work? My first attempt was actually with a space heater!