1: Put a large pan on medium heat and add 1 litre whole milk, 80 g butter, salt and pepper.
2: Heat until just simmering and the butter is completely melted.
3: In a bowl, use a whisk to mix together 250 g couscous (fine or coarse), the grated 100 g Parmesan (Parmigiano Reggiano) and ½ teaspoon grated nutmeg.
4: Tip this mixture into the hot milk off the heat, and mix with a whisk.
6: Put back on low heat and continue whisking until smooth. Change the whisk for a soft spatula and keep the pan on low heat for a further 3 or 4 minutes to dry the mixture out.
7: Take off the heat and transfer about a third of the mixture onto a sheet of stretch plastic film. Leave to cool for 5 minutes.
8: Roll up in the film and shape into a sausage about an inch and a half (4 cm) thick. Tie the ends with string.
9: Use up the rest of the gnocchi mixture like this. Lay the sausages on a baking sheet and refrigerate for about 2 hours.
10: Preheat the oven to 360°F (180°C). Generously butter a gratin dish.
11: Take the plastic film off the dough sausages...