If the unresponsive victim breathing the best position for the victim is?

Yes you should put a victim in a recovery position when victim is unresponsive and breathing.

if you cant see their chest moving, you should put your cheek next to their mouth/nose and see if you can feel any breath. if you don't feel anything, call 911. You can and should ALSO listen and...

Look, listen, and feel for breathing.

Lay the victim on his back and gently tilt their head back.          

Use the head tilt-chin lift