Benne seed is the Gullah Geechee name for sesame seed, brought to the American South by enslaved West Africans, whose languages used "benne" for the seed; it's the same plant grown throughout Africa and Asia, but the name specifically marks its place in traditional Southern U.S. cooking.
In the South, benne seeds are toasted and worked into benne wafers, breads, and cookies. Elsewhere, sesame appears throughout Asian cooking -- in Chinese stir-fries and Japanese goma dare dressing -- and in Middle Eastern and North African cooking, ground into tahini or scattered over breads. Toasting brings out its nutty flavor, which pairs well with soy sauce, honey, ginger, and garlic.