It refers to vanilla beans originating from the islands of Madagascar, Runion (formerly le Bourbon, hence the name), and other islands in the Indian Ocean like the Comoros. Characterized by a rich, creamy, and intensely vanilla flavor profile, these beans are sought after for their distinct aroma and sweetness. Bakers frequently use it in desserts where the vanilla flavor is central, such as crme brle or vanilla ice cream.
Its significance lies in its superior quality and flavor complexity compared to vanilla beans from other regions. The curing process used in these regions contributes to its unique characteristics, enhancing the vanillin content, which is the primary flavor compound in vanilla. Historically, the French influence in these regions led to the development of the specific cultivation and curing techniques that are still employed today, resulting in a product prized globally.