Note: Use pasteurized eggs. The same amount of bouillon may be used for stock.

Scrub potatoes, rinse.

Boil potatoes in their jackets until tender.

Let potatoes cool slightly.

Peel and cut potatoes into 1/4 inch slices.

Cook bacon in a pan until crisp.

Add diced onion to the bacon and stir until the onion is transparent.

Add vinegar, stock, salt, pepper, and sugar to the pan.

Stir the mixture well.

Let the mixture come to a boil.

Stir in the beaten egg yolk to create a creamy sauce.

Remove the pan from the heat.

Pour the hot bacon-onion-egg mixture over the sliced potatoes.

Toss gently to combine.

Serve warm.