Mustard Green and Pork Soup

Hakkas love mustard greens—fresh, salted, pickled, and preserved. This quick soup shows off the flavor power of fresh mustard greens. As the greens simmer, their pungency leaches into the broth to contrast with the rich pork. Use almost any type or maturity of mustard greens, from leafy to broad-stemmed varieties. I prefer the young stalks of Chinese mustard greens that I find at the farmers’ market, but curly southern mustard greens from the supermarket also work well.