2 pounds red potatoes, cut into 1-inch chunks
1 pound sweet potatoes, peeled and cut in 1-inch chunks
1/4 cup red wine vinegar
1 tablespoon spicy brown mustard
1 1/4 teaspoons salt
1/2 teaspoon pepper
1/2 cup reduced-fat mayonnaise
1/4 cup 2% milk
2 celery ribs, chopped
1 small red onion, chopped
1/3 cup minced fresh parsley


In a large saucepan, cook the red potatoes, covering it with water. Once boiling, lower heat and cook covered for about 2 minutes. Add the sweet potatoes and let it come to a boil. Bring heat to low and cover, cooking for another 10 minutes.
Combine the vinegar, mustard, salt and pepper into a large bowl. Add the drained potatoes into the mixture and mix slightly until coated then cool.
Mix mayonnaise and milk. Blend in the celery, onion and parsley. Stir this mixture into the cooled potato mixture. Serve immediately or chill until serving.