Cauli and Yam Mash

This not a recipe per se, but an idea.  I made yams a while back when my boys were visiting and took some and mashed it in with our cauli-mash.  Boy was it good - much thicker and more substantial-tasting!  Definitely more carby but not as much as eating yam or sweet potato by itself.  So for a special occasion, I highly recommend it. I know others do the same thing using rutabagas, but I can't find that over here.