Lift radicchio mixture from pan, add to trenette in baking dish, and mix lightly Then add cream, nutmeg, white pepper, and wine to pan. Increase heat to high and bring to a boil; boil, stirring often, until reduced to 1 1/4 cups. Remove from heat and add fontina cheese; stir over medium heat until cheese is melted. Mix in 1/2 cup of the Parmesan cheese, then pour sauce over trenette mixture. Sprinkle with remaining Mi cup Parmesan cheese.