Combine the stock and cream in a heavy saucepan and bring to a simmer. Add the nutmeg, salt, and pepper. Whisk in the polenta and semolina and cook over very low heat, whisking regularly, until the grains are soft, about 8 minutes. Whisk in the cheeses. Serve immediately or reserve.

To encourage polenta to come cleanly out of the pan, cook over medium heat. Run a spatula or wooden spoon around the sides of the pan to clean off the polenta. Do not stir, but wait and watch for a few seconds until a large bubble begins to form and pushes the polenta upward. Pour immediately into a warm dish.

The polenta can be made ahead and reheated: add 1/4 to 1/2 cup water or stock, cover the dish, and reheat in the microwave or over low heat. Whisk well before serving. Grate a dusting of parmesan over the top just before serving.

Chef's note: You can add 2 tablespoons of garlic oil to the cooking liquid to add a subtle garlic flavor to the polenta.

Variation for Firm Polenta: Proceed as directed, but increase the amounts of polenta and semolina each to 1/2 cup, giving a total of 1 cup dry to 3 cups liquid, a ratio of one to three. It will not take longer to cook. Serve immediately or pour onto a parchment-lined baking sheet and spread into an even 1/2-inch-thick layer. Let cool. Cover and refrigerate for several hours or overnight. Cut into thick fingers or triangles and reheat or freeze. To reheat, sprinkle lightly with freshly grated Parmesan cheese and place in a preheated 500°F oven until lightly browned, about 6 minutes. Or fry in butter or olive oil.

Variation for "Pumpkin" Polenta: Proceed as directed for soft polenta, adding 1 cup Roasted Winter Squash at the end of cooking and before the cheese. Omit the Fontina and increase the Parmesan to 1/2 cup. If you want to go to heaven, serve the pumpkin polenta on its own as an appetizer or supper dish drizzled with white truffle oil.