Vanilla beans are the product of the world's only fruit-producing orchid, the Vanilla planifolia.

Vanilla beans are the product of the world’s only fruit-producing orchid, the Vanilla planifolia.

In fact, the vanilla orchid (Vanilla planifolia) is the only orchid that produces an edible fruit. It was originally discovered climbing among the trees in Mexico and was later introduced to other warm tropical and subtropical regions of the world.

Source, Image credit: Malcolm Manners