In a medium saucepan, cook potatoes in salted water until tender, about 15 to 20 minutes. Remove from pan and dice. Place in a medium bowl and add tomatoes green onions, and salt and pepper to taste. Toss gently. Set aside. In a small mixing bowl combine vinegar, mustard and cayenne pepper. Add oil in a thin stream, heating constantly. Stir in parsley. Add dressing and bacon to potatoes and toss gently. Allow potatoes to absorb dressing at least 15 minutes before serving.
Cajun Country -- New Iberia, Louisiana