You wouldn’t steam your steak, but steaming fish is actually okay. It’s a great way to keep fish moist. And you can do it easily on the grill by cooking it in a foil packet. Simply stack two 20-inch sheets of foil. Coat the center of the top layer with cooking spray. Layer your ingredients on the foil. (You can add other things to your packet like thinly sliced veggies or lemon.) Bring the short ends of the foil together, leaving enough room in the packet for steam to gather and cook the fish. Fold the foil over and pinch to seal. Pinch seams together along the sides. Place the packets on a gas grill over medium heat or on a charcoal grill 4 to 6 inches from medium coals. Cover the grill and cook just until the packet contents are done (about 8-10 minutes for a salmon fillet or equivalent, about half that for shrimp and scallops). Handle the hot packets with a large spatula or oven mitts. Carefully open both ends of the packet and allow the hot steam to escape.