2 c. cooked potatoes, sliced
6 slices bacon, diced
1/2 c. onions, diced
1/2 c. vinegar
1/2 c. stock
1 tsp. salt
1/4 tsp. black pepper
1 tsp. sugar
1 egg yolk, beaten

Cook bacon over high heat until crisp. Add the onion and saute until golden and then the vinegar, stock and seasonings. Allow to come to a boil, stirring constantly. Carefully stir in the egg yolk. Pour over the potatoes, toss and serve.