Combine the cream, butter shallot garlic, nutmeg, cinnamon and salt in a saucepan and bring to a gentle simmer for 1 minute. Remove rom heat and allow to sit for 15 minutes.
Preheat oven to 400 degrees. Lightly butter an 11 x 7 baking dish.
Grate the potatoes and squash on the large holes of a box grater or in the food processor. Combine and toss with the sage. (You will have about 10 cups).
Wipe the blade or grater clean and grate the cheeses; combine them in a bowl. (You will have a little over 3 cups).
Press half the potato-squash mixture in the bottom of the pan; top with half the cheese. Place the remaining potato-squash over the cheese and press lightly; top with the remaining cheese. Pour the cream through a fine mesh strainer over the casserole. Garnish with a few sage leaves if desired.
Coat a piece of foil with cooking spray and wrap it loosely (sprayed side down) over the top of the casserole. Bake 40 minutes. Remove the foil and bake until the top is golden brown and the potatoes are tender, about another 20 minutes. Allow to cool slightly before serving.
Makes 12-14 servings
* Miss Margie can help eliminate stress related to preparing and serving the feast; any tension related to family relationships is strictly up to the reader to control.