Chicken feet give this broth its ultra-luxurious texture (and they're great for your skin and joints, too!). Look for them in the freezer section of some grocery stores, or ask at the butcher's counter.
10 cups water
One (4-lb) chicken, or a combination of chicken bones & parts, preferably including some chicken feet
10-12 large dried Chinese (shiitake) mushrooms
6 pieces fresh ginger the size of a quarter, smashed lightly with the flat side of a cleaver or knife
6 whole green onions, lightly smashed, ends trimmed
1 cup rice wine or sake
Kosher salt
½ lb baby bok choy, quartered lengthwise (optional)