-
In a heavy saucepan, heat wine, juices, vinegar, and shallots over medium heat and simmer until the liquid has been reduced by half.
-
Add in the cream, and bring to a boil for 2 minutes.
-
Whisk in the butter quickly, adding several pats of butter at a time and adding more when the previous amount has been incorporated.
-
Toss in the grapefruit and serve immediately.