Chorizo Soup with Shiitake Mushrooms & Chickpeas (serves 4)

INGREDIENTS: – 1/3 pound fresh lamb or pork chorizo – 1/4 pound shiitake mushrooms, caps only, roughly chopped – olive oil – 1 small red onion, finely chopped – 2 cloves garlic, finely chopped – 15-ounce can chickpeas, drained – 4 cups beef stock – 2 tablespoons cider vinegar – salt and freshly ground pepper,…