Preparation Cover potatoes with salted water in large pot. Cover and boil gently until potatoes are tender but still hold their shape, about 30 minutes. Drain and cool slightly. Peel and cut into 1-inch pieces. Transfer potato pieces to large bowl. Stir vinegar and mustard in medium bowl until mustard dissolves. Mix in mayonnaise, sour cream, sugar and paprika. Add bell peppers and celery. Pour dressing over warm potatoes; toss gently. Season with salt and pepper. Cool completely. (Can be prepared 1 day ahead. Cover and refrigerate.) Garnish with sliced eggs and chopped parsley. Serve at room temperature.
Preparation Cover potatoes with salted water in large pot. Cover and boil gently until potatoes are tender but still hold their shape, about 30 minutes. Drain and cool slightly. Peel and cut into 1-inch pieces. Transfer potato pieces to large bowl. Stir vinegar and mustard in medium bowl until mustard dissolves. Mix in mayonnaise, sour cream, sugar and paprika. Add bell peppers and celery. Pour dressing over warm potatoes; toss gently. Season with salt and pepper. Cool completely. (Can be prepared 1 day ahead. Cover and refrigerate.) Garnish with sliced eggs and chopped parsley. Serve at room temperature.