Mornay Sauce

Method

1. Melt the butter in a saucepan.
2. Add the flour and let it absorb the liquids.
3. Pour in the milk and cook, stirring constantly, until the béchamel thickens and almost reaches a boil.
4. Remove from heat and add nutmeg, pepper, and salt. Mix well.
5. Add the egg yolk, cream, and Parmigiano Reggiano. Stir.
6. Return to the heat for a few moments to cook the egg.
7. Let cool slightly before using.