Direction :

1. Put the milk in a heavy-bottomed saucepan and turn on the heat to medium low. When the milk forms a ring of tiny, pearly bubbles, but before it comes to a boil, turn down the heat to low, and add the semolina flour, pouring it out of a clenched fist in a very thin, slow stream and, with a whisk in your other hand, beating it into the milk. (If you find the clenched fist, awkward, pour the semolina in slowly using a liquid measuring cup.)
2. When all the semolina has gone into the pot, stir it with a long-handled (or not) wooden spoon. Stir continuously and with thoroughness, bringing the mixture up from the bottom and loosening it from the sides of the pot. Be prepared for some resistance because the flour and milk mixture quickly becomes very dense. In little more than 15 minutes and less than 20, the mixture forms a mass that comes cleanly away from the sides of the pot.
3. Remove from heat, let it cool just slightly, for about a minute, then add two-thirds of the parmesan, 2 teaspoons salt, the yolks, and the 2 tablespoons of butter to the batter. Mix immediately and rapidly to prevent the yolks from setting.
4. Moisten a laminated or marble surface with cold water (or run a sheetpan under water; then hold it over the sink and let the water drain out) and turn the gnocchi batter out over it, using a spatula to spread it to an even thickness of about ⅜ inch. Dip the spatula in cold water from time to time as you use it. Let the batter cool completely. (You can stick the sheetpan in the fridge for 30 minutes at this point to help it cool down.)
5. Preheat oven to 400ºF. When the batter has cooled off completely, cut it into disks, using a 1.5-inch biscuit cutter or a glass of approximately the same diameter. Moisten the tool from time to time in cold water as you us it. (Do not discard the trimmings. See note above.)
6. Smear the bottom of a bake-and-serve dish (I’ve used a 9×13-inch baking dish and a 10-inch round baking dish, which was actually a little too small.) lightly with butter. On the bottom, arrange the gnocchi in a single layer, overlapping them roof-tile fashion. Sprinkle with remaining parmesan and dot sparingly with butter. Bake on the uppermost rack of the preheated oven for 15 to 20 minutes until a light, golden crust has formed. After removing from the oven, allow to settle for 5 minutes before bringing to the table and serving directly from the baking dish.