Prepare an ice bath in a medium bowl and set aside.

Combine the heavy cream, half of the sugar, and the vanilla beans (and scraped seeds) in a medium saucepan and bring to a boil.

Whisk the egg yolks together with the remaining ¼ cup sugar in a small heatproof bowl and slowly whisk in 1 cup of the hot cream mixture. Reduce the heat to low and little by little, whisk the egg mixture into the hot cream mixture in the saucepan and cook, stirring constantly, until the mixture thickens enough to coat the back of a spoon. (Take care not to overcook or the mixture will curdle.) Strain the sauce immediately into a clean bowl set over the ice bath and stir until the sauce is cooled to room temperature.  Chill before serving.