You'll need an ice cream maker for this recipe. It should be prepared ahead of time according to the manufacturer's directions.
Combine the heavy cream, milk, egg yolks, sugar, and salt in a saucepan. Bring to a steep over low-medium heat, but don’t let it boil.
2 cups heavy cream, 1 cup whole milk, 5 large egg yolks, 1 cup granulated sugar, ¼ teaspoon salt
Stir consistently and continue to cook for approximately 8 to 10 minutes until the custard thickens slightly. It should lightly coat the back of a spoon when ready. (Run your finger across the back of the spoon; if the custard doesn't come back together, it's done.)
Remove from heat then stir in the vanilla extract.
1 tablespoon pure vanilla extract
Pour the custard through a mesh strainer into a heat-safe bowl. Place the bowl of custard into a larger bowl of ice for about 30 minutes to 1 hour to cool.
After the custard cools considerably, cover it with plastic wrap. The plastic wrap needs to touch the top of the custard to prevent a skin from forming.
Transfer it to the refrigerator to cool completely, about 2-4 hours. Once cooled, the custard will have a thin, pudding-like consistency.
Pour it into the prepared ice cream maker. Churn according to the manufacturer's instructions until the ice cream sets enough to transfer it to a freezer-safe container. It should be firmer than soft-serve consistency.
Freeze until the ice cream is completely firm. (Ours took 8 to 10 hours.)