1 yolk from hard boiled egg
1 raw egg yolk
1 1/2 tbsp. lemon juice
1/2 tsp. mustard
1/4 tsp. salt
Dash of white pepper
1 1/2 tsp. sugar
3/4 c. heavy cream

Pass cooked egg yolk through sieve and mix with raw egg yolk and lemon juice. Add seasonings. Fold in whipped cream very carefully and serve immediately. If sauce shows sign of curdling, add small amount of heavy cream and stir until smooth.