Yam Gratin with Gruyere

Wonderful yam recipe Kay got after tasting it at Wegmans.  She used
1/2 cream and 1/2 milk, which made it not real heavy but still very
very tasty.  A great find!

2 C heavy cream (or 1 each, heavy cream and milk)
1 tsp salt
3 lbs yams, peeled
1/2 C shredded Grand Cru Gruyere ( or any tasty gruyere)

Preheat oven to 350
1)  Spray baking dish w. nonstick spray.  Place baking dish on baking tray
2)  Stir together heavy cream and salt in large bowl.  Using
mandoline, slice yams into bowl, coating slices with cream mixture as
you work.  (Kay sliced hers into 1/4" or so slices.
3)  Layer 1/3 yams in baking dish. Sprinkle w 1/2 of cheese.  Repeat
with another 1/3 yams and remainder of cheese.  Top with remaining
yams.  Pour any remaining yam-cream mixture over top.
4)  Bake uncovered on center rack of over 30 mins.  Remove from oven.
5)  Press fork of spatula carefully against top layer to allow liquid
to flow over top.  Replace pan in over; bake 40-45 mints or until yams
are tender.  REmover from oven;  let rest 15 mins.