I suppose it is neither a taco or a sand which, however it lives within the sandwich family. What's weird is if we take the inner radius as it runs towards zero it would look no different to a sandwich (save the weirdly thick bread that looks similar to a burger), but it would be topologically different shape.

I suppose it depends on if you consider a bagle split more naturally a sandwich or not, and, if so, then it matters if the if the space of the filling being connected matters or not.