Mom Staples Hot Potato Salad

4 cups cooked sliced potatoes
1/4 lb bacon - raw and cut into small pieces
3/4 cup chopped onion
2 Tbsp flour
2 tsp salt
1 egg
1/4 cup sugar
1/4 cup cider vinegar
1 cup water
1/4 cup parsley, fresh or dried
1 tsp celery seed

Fry bacon until crisp.  Remove from fat
Fry onion in fat until tender.  Remove from fat
Put flour and salt in fat to clear it
Mix egg and remaining ingredients together.  Put in frying pan
Pour hot mixture over potatoes