True vanilla ice cream

Ingredients: 1 1/2 cups heavy cream,1 cup whole milk,1/2 cup sugar,Pinch of kosher salt,1 vanilla bean or 1 teaspoon vanilla extract,5 egg yolks
Instructions:

1. Combine heavy cream, whole milk, 1/4 cup sugar and salt in a medium saucepan. Split vanilla bean lengthwise and scrape in seeds; add pod (or use 1 teaspoon vanilla extract). Bring mixture just to a simmer, stirring to dissolve sugar.
2. Remove from heat. If using vanilla bean, cover; let sit 30 minutes.
3. Whisk 5 large egg yolks and 1/4 cup sugar in a medium bowl until pale, about 2 minutes. Gradually whisk in 1/2 cup warm cream mixture.
4. Whisk yolk mixture into remaining cream mixture. Cook over medium heat, stirring constantly, until thick enough to coat a wooden spoon, 2 to 3 minutes.
5. Strain custard into a medium bowl set over a bowl of ice water; let cool, stirring occasionally. At this point, you can transfer the mixture to a bowl and cover it by putting plastic wrap directly on the top of the custard. It can cool overnight in the fridge and processed in the morning.
6. Process custard in an ice cream maker according to manufacturers instructions.
7. Transfer to an airtight container; cover. Freeze until firm, at least 4 hours and up to 1 week.

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