Directions:
1. Stir together sugar and salt in small, heavy saucepan.
2. Add egg yolks and stir to blend. Scald 1/2 cup cream with milk, whisking constantly and vigorously, then gradually add to yolk mixture.
3. Cook over low heat, stirring constantly, until just before boiling point (170 to 180 degrees), 7 to 8 minutes.
4. (Steam will begin to appear). Immediately stir in Grand Marnier and vanilla.
5. Strain mixture. Cover and chill until cold. Shortly before serving, whip remaining 1/2 cup whipping cream and fold into sauce.