Step 1

In a small pot, whisk the yolks and sugar together for 2 to 3 minutes, or until the sugar is fully dissolved and the yolks are more of a pale yellow.

Step 2

Whisk in the milk until smooth.

Step 3

Place the pot over medium-low heat, and heat, whisking often, for 10 to 20 minutes, or until lightly thickened to coat the back of the spoon. Do not let the mixture reach a boil. The time will depend on your pot and stove, but it should be slowly heated.

Step 4

Remove he pot from the heat and whisk in the salt and vanilla.

Step 5

Let the sauce cool completely before storing in an airtight container in the refrigerator. It will thicken a little more if chilled for a day.