8-9 med. potatoes, cooked, peeled & diced
2 slices bacon, diced
1 med. onion, chopped & divided in 2
3 stalks celery
1/4 c. cider vinegar
3/4 c. water
3 tbsp. sugar
3 egg yolks
1 1/2 tbsp. prepared mustard

Fry bacon and 1/2 onion until crisp. Drain fat. Add vinegar and water. Add sugar, stir until dissolved. Mix together egg yolk and mustard and add to frying pan. Boil 1 minute until thickened. Pour over potatoes, 1/2 onion and celery; mix well. Serve warm or cold.