1. Bring milk, cream of coconut, coconut, and vanilla bean and seeds to a simmer in a medium pan over medium-high heat. Remove from heat. Let steep 1 hour.

2. Put egg yolks, sugar, cornstarch, and salt in the bowl of an electric mixer fitted with the whisk attachment; mix on medium-high speed until thick and pale, about 5 minutes. Reheat milk mixture until hot. With mixer on medium-low speed, slowly pour in milk mixture. Transfer to saucepan. Cook over medium heat, whisking constantly, until boiling. Strain through a fine sieve. Let cool completely. Whisk before using.