Rum Sabayon

Directions

1. 1
   In a large metal bowl whisk together yolks, sugar, rum, and 1/4 cup cream.
2. 2
   Set bowl over a saucepan of simmering water and cook mixture, whisking constantly, until frothy and whisk leaves distinct marks.
3. 3
   Set bowl in a larger bowl of ice and cold water and cool sauce, stirring gently with a rubber spatula, until cold.
4. 4
   In a bowl with an electric mixer beat remaining 3/4 cup cream until it just holds stiff peaks and fold into sauce gently but thoroughly.
5. 5
   Sabayon may be made 1 day ahead and chilled, covered.