Line the bottom of a 15 1/2 x 10 1/2-inch baking pan with aluminum foil. Generously
oil the foil.
Heat milk, salt, nutmeg and pepper in heavy saucepan over medium-high
heat just to simmering. Do not boil; reduce heat to medium-low. Begin whisking or
stirring milk briskly and add semolina in thin steady stream, taking care not to
let lumps form. Cook, stirring frequently, until thick enough for spoon to stand
upright and unsupported in center of mixture, 5 to 10 minutes.
Reduce heat to low; continue cooking, stirring constantly, until very thick,
about 5 minutes longer. Remove from heat.
Add egg yolks, 1/4 cup of the cheese and 2 tablespoons of the butter to semolina
mixture; stir until butter is melted and mixture is smooth. Transfer mixture to
prepared pan. Pat out with spatula to 3/8 inch thickness. Refrigerate uncovered
until cold, at least 1 hour.
Heat oven to 425 degrees F. Turn mixture out of pan onto flat surface; peel off
foil. Cut gnocchi out of mixture with 2-inch round cutter. Arrange gnocchi overlapping
in 10-inch square shallow flameproof baking dish.
Melt remaining 4 tablespoons butter. Drizzle melted butter over gnocchi. Sprinkle
with remaining 1/4 cup cheese. Bake until tops of gnocchi are crisp and golden,
20 to 25 minutes.
Place under broiler about 4 inches from heat, until light brown,
1 to 2 minutes.