Definitely a tort, just like the little baby doe in my avatar thing. Torts are my second favorite color of rabbit...my most favorite being Broken Torts, LOL!!!
We have a black tort this past litter that is the opposite. It has a strip of brown down it's back and the rest is the black/grey color. When you aren't breeding show quality to show quality of the same color you can get a lot of variation. Especially with mutts.