Keep an eye on this delicate custard sauce: It cooks very quickly.
- 2 cups milk
- 1 split vanilla bean
- 6 egg yolks
- 1⁄4 cup sugar
Place milk and vanilla bean in a heavy-bottomed saucepan and bring just to a simmer over medium heat.
Meanwhile, whisk together egg yolks and sugar in a mixing bowl. Reduce heat to low and slowly whisk 1⁄2 cup hot milk into egg mixture, then whisk egg mixture into remaining hot milk. Cook, stirring constantly with a wooden spoon, until mixture is thick enough to coat the back of the spoon, about 5 minutes.
Remove from heat, strain through a fine sieve, and transfer to a mixing bowl. Stop the cooking by placing bowl into a larger bowl of ice water. Scrape seeds from vanilla bean into custard and discard pod. Cool to room temperature then refrigerate until cold. (Store in refrigerator for up to 3 days.)