Preheat the oven to 425 defrees. Butter a jelly roll pan that has 3/4 inches sides.
In a 3 to 4 quart sauce pan, heat the milk, salt, and 6 Tbs of the butter nearly to the boiling point over medium heat.
Whisking vigorously, add the semolina in a thin stream and cook for about a minute, switching to a wooden spoon as the batter thickens.
Remove from the heat and stir 1/2 cup of the grated cheese, then beat in the egg yolks. Working quickly pour the batter into the prepared pan and spread to a thicknes off 1/2 inch. Allow to cool and cover with plastic until ready to cook.
Using a 3-inch diameter water glass, cut a rows of rounds across the sheet.
Arrangein a well buttered baking dish. If there is any butter left, mealt it and pour on top of gnocchis. Sprinkle with the remaining 1/2 cup of grated cheese. Place in the oven and cook 15 to 20 minutes, or until the top is light golden brown. Remove and serve inmediately.