Pork with Turnips, Tomatillos, and Greens

This recipe is loosely based on one by Rick Bayless that my parents make with big chunks of pork shoulder their butcher calls “pork cushions”; I’ve never seen that terminology used myself, but it feels appropriate. Bayless’s process is of course a bit more complicated, and he uses potatoes and wild greens instead of turnips, but I really love the bite and faint bitterness of turnips and their greens (which mellow considerably over the course of a day in the slow cooker).