The brownie variation that uses brown sugar and vanilla rather than chocolate in the batter is a blondie.
A blondie is a dense dessert bar closely related to the chocolate brownie, but its characteristic flavor comes from brown sugar and vanilla instead of cocoa or melted chocolate. The substitution gives blondies their pale golden color and a rich caramel-like taste. Butter, flour, eggs and baking powder are also common ingredients.
The name can be confusing because blondies were historically connected to the broader meaning of “brownie.” Early brownie recipes were not always chocolate-based: some used molasses or brown sugar and resembled the modern blondie. As chocolate brownies became the dominant type in the early twentieth century, the older light-colored version was increasingly called a “blonde brownie,” later shortened to “blondie.”
A blondie is not simply a brownie with white chocolate. White-chocolate blondies are popular, but white chocolate is an optional addition rather than the defining ingredient. Likewise, a brookie combines brownie and cookie elements, while a lava cake is defined by its molten center.