Famously featured in Caesar salad, romaine lettuce has a sweet, gentle flavor and a crisp bite that stands up well to punchy flavors. The hearts (the interior, lighter colored leaves) are especially crunchy and refreshing and will stay crisp even with a warm dressing, making romaine a good choice for main-course salads. Baby romaine leaves, both red and green, are often packaged as a salad mix, and are also found in mesclun mixes. The flavor of these immature leaves is less bitter than mature romaine, and not as juicy.
1 romaine heart = 3 to 4 cups pieces (1/2 inch strips)
You can use iceberg lettuce instead.
Heads of Romaine should feel be tight and feel heavy for their size.
Remove and discard any darkened or wilted out leaves. If serving in wedges, trim away the root end but leave it intact. Otherwise cut it off. Gently wash the leaves and pat them dry before tearing or shredding as you recipes directs. Unlike tender leaf lettuces, romaine can stand up to a sharp knife, which makes quick work of cutting the leaves (crosswise is best) in into strips for salads.
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.