In a bowl, whisk egg yolks, sugar and kosher salt together until thick and light yellow.
Heat milk in a large sauce pan just until simmering.
Temper egg mixture by adding a ladle of hot milk to yolks and sugar. Slowly whisk and continue adding milk to yolks until about 1/2 is added.
Then add back egg and milk mixture to pan, continuing to whisk. Bring custard base back to a gentle simmer over medium heat, whisking constantly until custard is thicker, and coats the back of a spoon, about 6-8 minutes.
Remove base from heat and whisk in pistachio paste, vanilla extract, and brandy.
Strain gelato mixture through a Fine Mesh Sieve, into a large bowl over an ice bath to cool base. Chill the gelato base in the refrigerator for a few hours. Chilling will help the gelato freeze more quickly.
Follow your ice cream manufacturer's instructions to churn ice cream.
Pack ice cream in airtight container and freeze several hours or overnight to cure