Preparation Stir together vinegar, onion, apple, soy sauce, and sugar until sugar has dissolved, then stir in oil. Just before serving, toss watercress with enough dressing to coat. Quarter, pit, and peel avocado, then cut crosswise into 1/4-inch-thick slices. Gently toss with watercress. Cooks' notes:·Watercress can be trimmed 1 day ahead and chilled in a sealed bag lined with damp paper towels. ·Dressing can be made 2 days ahead and chilled, covered. Stir or shake before using.
Preparation Stir together vinegar, onion, apple, soy sauce, and sugar until sugar has dissolved, then stir in oil. Just before serving, toss watercress with enough dressing to coat. Quarter, pit, and peel avocado, then cut crosswise into 1/4-inch-thick slices. Gently toss with watercress. Cooks' notes:·Watercress can be trimmed 1 day ahead and chilled in a sealed bag lined with damp paper towels. ·Dressing can be made 2 days ahead and chilled, covered. Stir or shake before using.