From the book Il Gelato Secondo Matteo, by Carlo Correra.
1 quart fresh pasteurized whole milk
7 ounces granulated sugar
7 ounces sugar syrup (about 1 cup)
Pinch of salt
A few drops of vanilla
7 ounces freshly grated Parmesan cheese from Parma
Combine all the ingredients except for the cheese in a bowl, whisk well, and then transfer to a pot. Heat the mixture to 185 degrees F. and stir well until thickened, about 5 or 6 minutes, taking care that it does not boil. Remove from the heat and allow to reach room temperature. Mix in the cheese and transfer to an ice cream maker, then follow the manufacturer’s instructions.