By Mark Bittman, author and columnist for the New York Times
Time: 15 minutes
Yield: 4 servings
1. Place the stock in a large skillet that can be covered and turn the heat to high. Let it boil and reduce by about half while you prepare the leeks. Trim the leeks of the root and green end; cut the white part in half the long way and rinse thoroughly. Chop each half into 1/8- to 1/4-inch thick semi- circles, adding them to the boiling broth as you cut them.
2. When all the leeks are added, cook for another minute. Add salt and pepper and stir, then add the fish. Cover and turn off the heat, or keep the heat at an absolute minimum. Uncover and check the fish after 3 minutes; it is done when a thin-bladed knife encounters no resistance. Continue to check every minute until the fish is done.
3. Serve the fish with the leeks and some broth spooned over it; top all with a sprinkling of coarse salt.
Adam Rapoport, editor in chief of Bon Appetit magazine and the website www.bonappetit.com, knows his way around a grill. He has edited an entire book on the subject: The Grilling Book: The Definitive Guide from Bon Appetit.