Beat egg yolks and egg in small mixer bowl on high speed until thick and lemon colored, about 3 minutes.
Gradually beat in sugar, scraping bowl occasionally.
Beat in wine and salt on low speed.
Pour mixture into top of double boiler.
Add enough hot water to bottom of double boiler so that top does not touch water.
Cook over medium heat, stirring constantly, until slightly thickened, about 5 minutes.
Remove from heat.