YAM AND CASHEW CASSEROLE

2 1/2 lbs sweet potatoes or yams, scrubbed
1 t cinnamon
1/4 t salt or to taste
1 egg
About 1/4 C pineapple juice
About 1/4 C apple juice
1/4 C granulated sugar, or to taste
3 T butter at room temp, divided
1/2 C salted cashews, coarsely chopped
Cook sweet potatoes in boiling water until tender (30 min). Drain and let cool, peel and place in large bowl. Using an electric mixer or potato masher (not a food processor), beat yams until almost smooth. Add cinnamon, salt, egg, juices, and sugar. Continue to beat until mixture is moist and fluffy, adding more juice if needed. Beat in 2 T butter. Season to taste with more salt and sugar, if desired. Spread in shallow 1-quart baking dish.
Melt rest of butter in small frying pan over med heat. Add cashews and toast about 3 min. Sprinkle over potato mixture. Bake uncovered at 375, until heated through.