Back Face Culling to make an Outline

So if you have two spheres, and one is slightly larger than the other, then you can flip the normals of it and enable back face culling, basically making it only visible from one side. This should then give the smaller sphere a sort of outline, much like a toon shader, but WAY simpler.

How can you do this in blender (2.79)?
Blender render is preferred, but cycles render is ok

With nodes, in either engine. Geometry node front/back (bi), or backfacing (cycles).

Which parts of the Geometry node do I use? Also, where do I plug them into on the output node?