Prized for its a crisp texture, the fact that iceberg lettuce doesn't have a ton of flavor is almost beside the point. Its audible crunch is welcome on sandwiches and shredded to serve with Tex-Mex food. A wedge of icerberg is a great foil for a chunky blue cheese dressing (bacon optional) while torn leaves added to a salad of other greens provide a welcome and refreshing counterpoint. A crisphead lettuce, iceberg leaves grow in a tight ball.
You can substitute Romaine lettuce, especially the hearts, which are nice and crisp.
Look for heads that are heavy for their size with unblemished outer leaves.
Remove any outer leaves that seem witled, usually at least one or two should go. To easily core a head of iceberg, put it on the counter with its root end up. With the palms of your hands press down firmly on the root; the core will then come right out. Because the head is so tight, the leaves should be free of any grit. But give them a wash under cool water if need be and dry them well.
Whole heads should last for at least a few days wrapped and refrigerated. Pack washed and dried leaves loosely in a zip-top bag lined with paper towels, gently squeeze out most of the air, and seal.