German-Style Potato Salad

2 pounds (6 medium-sized) white new potatoes or Yukon gold 1 quite small, mild red onion 10 slices bacon 1 egg, slightly beaten 1/2 cup sugar 1 T. all-purpose flour 1/2 tsp. each dry mustard and salt 1/3 cup each water and white wine vinegar Salt and pepper to taste Dry or chopped fresh parsley […]