What is poured over the steamed milk in a Venti white hot chocolate?

In a Venti white hot chocolate, the addition to the steamed milk is milk foam. This foam is typically created by steaming the milk, which introduces air into it, resulting in a creamy and velvety texture that enhances the overall experience of the drink. The foam serves not only as a decorative element but also contributes to the drink's mouthfeel, making it smooth and enjoyable.

The other options do not accurately describe what is poured over the steamed milk in this particular drink. While cream, chocolate syrup, or caramel drizzle are indeed used in various other beverages, they do not specifically pertain to the traditional preparation of a white hot chocolate at Starbucks. This distinction is important for understanding how to correctly assemble this drink and appreciate the role of each component in its flavor profile.