Heat the cream in a small saucepan over medium
heat until just simmering. Add two-thirds of the
cheese; stir until melted. Stir in the nutmeg and the
pepper. Remove from heat; cover to keep warm.
Preheat the oven to 400F. Butter an 8-inchsquare
baking dish; set aside. Bring a large pot of
water to a boil; add the salt. Add half the gnocchi;
when they rise to the top (after about 2 minutes),
continue to cook until tender, about 15 seconds
more. Transfer the gnocchi with a slotted spoon to
the buttered dish. Repeat the process with the remaining
gnocchi.
Pour the cheese sauce over the gnocchi, and gently
toss. Sprinkle the remaining cheese on top. Bake
the gnocchi until golden brown, about 25 minutes