3 tablespoons lemon juice
1 tablespoon rice wine vinegar
1 tablespoon Dijon mustard
Salt and freshly ground black pepper
1/4 cup drained capers
1/2 medium red onion, thinly sliced
1/2 cup extra-virgin olive oil
8 cups watercress (preferably the kind that’s already trimmed, rinsed, bagged)
6 ounces smoked salmon, torn or cut into bite-size pieces
Mix lemon juice, vinegar, mustard and a big pinch of salt and pepper to taste in a 1-quart Pyrex measuring cup. Add capers and onion; toss to coat. Slowly add oil, pushing onion aside and beating with a small whisk or fork to form a thick dressing.
Mix watercress and half the salmon in a large bowl. When ready to serve, pour dressing over watercress and salmon; toss to coat. Arrange on salad plates, garnishing each with remaining smoked salmon.