Heat the milk and cream. Heat the milk, cream, and ½ cup of sugar in a saucepan over medium heat until it's warm and steaming, about 170°F.
Whisk the egg yolks and sugar. At the same time, whisk the egg yolks and the remaining ¼ cup of sugar until they turn light yellow and mix well. You can use a hand mixer on low speed if you prefer.
Temper the eggs. Slowly pour half of the warm milk mixture, about half a cup at a time, while constantly whisking. Then, pour the egg mixture back into the saucepan with the remaining milk and cream.
Cook the custard. Heat the mixture over medium heat, stirring constantly, until it's warm, but don't let it boil. Then, take it off the heat and add a little salt and some vanilla extract.
Strain and chill the custard. Strain the custard using cheesecloth or a strainer. Immediately place it in the refrigerator to chill for 4-24 hours, until very cold.