Steps
- Prepare the ice cream maker according to its instructions. Measure 2 cups of heavy cream; whisk half with ¼ cup of unsweetened cocoa powder in a saucepan over medium heat.
- Bring to a boil, reduce to low heat, and simmer for 30 seconds, whisking. Remove from the heat; stir in 170g of chopped semisweet chocolate until smooth, then the remaining cream.
- Pour into a large bowl and set a fine-mesh strainer over it. In the saucepan, warm 1½ cups of whole milk, ¾ cup of granulated sugar, and ⅛ teaspoon of sea salt over medium heat.
- Beat 3 large egg yolks. Gradually whisk in about ½ cup of the warm milk mixture, then whisk the yolks back into the saucepan.
- Cook over medium heat, stirring constantly, until the custard lightly coats a spatula and reaches 170°F / 77°C. Strain into the chocolate cream.
- Stir in ½ teaspoon of vanilla extract. Cover and refrigerate for at least 6 hours, until thoroughly cold.
- Churn according to the machine's instructions for about 30-40 minutes, until thick. Transfer to an airtight freezer container and freeze for at least 6 hours, until firm.