Potato salad

1.In a large saucepan, cover potatoes with cold water; bring to boil. Reduce heat; simmer, covered, until tender. Drain; cut into 3cm pieces. Spread potato on a tray, sprinkle with vinegar; refrigerate until cold.

2.Make mayonnaise.

3.Combine potato in large bowl with mayonnaise, onion and parsley.

4.Blend or process egg yolks, juice and mustard until smooth. With motor operating, gradually add oil in a thin, steady stream; process until mixture thickens. Add as much of the warm water as required to thin mayonnaise.