Method
Heat the milk with the vanilla bean until steaming. Whisk yolks, sugar, cornstarch, and salt until smooth.
Slowly whisk half the hot milk into the yolks, then return everything to the saucepan.
Cook over medium heat, whisking constantly, until the custard boils and thickens. Continue whisking for 1 minute, then remove from the heat and whisk in butter and vanilla extract if using.
Strain into a shallow container, cover directly on the surface, and cool rapidly before refrigerating.
Notes
The full boil cooks the cornstarch and prevents a starchy aftertaste; whisk continuously to avoid scorching.
Related recipes and techniques
These are extensions, technique comparisons, or serving relationships; the complete recipe above remains usable as written.
- Fill a fully baked shell made from Flaky All-Butter Pie Crust.
- Use it between layers of One-Bowl Chocolate Cake.
- Spoon it over or between Crisp Belgian-Style Waffles for a plated dessert.