1. Spray baking dish 10x10 with nonstick spray 2. Place baking dish baking sheet. 3. Stir together heavy cream and salt in a large bowl. Slice yams using mandoline into bowl with cream coating slices with cream mix as you work. 4. Layer 1/3 of yams in baking dish. Sprinkle with half the cheese repeat with another1/3 and sprinkle with the rest of the cheese. Top with remaining yams and pour any remaining cream on top 5. Bake uncovered on center rack for 30 min. Remove from oven. 6. Press fork or spatula carefully against top layer to allow liquid to flow over crust. replace in oven and bake 30 min. 7. Remove and follow same procedure as above and return to oven again for 40-45 Min.