Combine vinegars and mustard in small mixing bowl. With whisk, gradually add olive oil until incorporated. Whisk in pepper to taste.
or
Combine lemon juice, vinegar and salt in small mixing bowl. With whisk, gradually add olive oil until incorporated. Whisk in pepper to taste and stir in chopped water cress.
Place greens, red pepper and snow peas in salad bowl. Toss with either the vinaigrette or water cress dressing. 4 servings.