It already has a groove for roads! It's the GOP and Christianity's fault we're not living there right now, we should destroy them immediately in the name of this unclaimed territory.
Here's my off the cuff guess : Back in the day when it was cooling, the poles cooled first, then the centripetal force caused by its rotation forced the inner molten nougat out to the surface where there was, for a time, a nougat belt that spun at a slower rate than the poles.