Winter Greens, Sunchokes, Carrots, Fennel, and Radishes with Grainy-Mustard Vinaigrette

Inspired by a salad I ate at Grüner, an Alsatian restaurant in Portland, Oregon, owned by Chris Israel, I use raw Jerusalem artichokes and other winter roots to give this salad color and crunch. I simplified the garnish by buying roasted and salted pumpkin seeds for scattering on top, but Chris turns homemade soft pretzels into croutons and tosses them with the salad. That’s easy enough to do if you make your own, happen to live in a big city with soft pretzels sold on street corners, or wa