Braised Lamb Shoulder With Potatoes and Fennel

2 tablespoons coriander seeds 2 tablespoons fennel seeds 1 tablespoon black peppercorns 4 large lamb shanks (about 5 pounds) 4 tablespoons olive oil, divided[...]

4 2-inch-thick lamb shoulder-blade chops (about 4 3/4 pounds total) 3 tablespoons butter 2 tablespoons olive oil 2 large red onions, coarsely chopped 6 large[...]