Combine the heavy cream, whole milk, and half of the sugar in a saucepan, then add the split vanilla beans and their seeds. Warm over medium heat, stirring gently, until the mixture is steaming and small bubbles form around the edges—avoid boiling.
While the milk warms, whisk together the egg yolks with the remaining sugar and a pinch of salt until the mixture turns pale and slightly thickened.
Remove the vanilla beans from the warm milk and slowly pour about half of the hot milk into the egg mixture, whisking constantly to temper the eggs.
Pour the tempered egg mixture back into the saucepan with the remaining milk, then cook over low heat, stirring constantly, until the custard thickens enough to coat the back of a spoon—about 5-7 minutes. You will notice it becomes slightly glossy and nappe-like.
Strain the custard through a fine-mesh sieve into a clean bowl to remove the vanilla bean remnants and ensure a smooth texture. Let it cool slightly.
Cover the bowl with plastic wrap, pressing it directly onto the surface of the custard to prevent a skin from forming, and chill in the refrigerator for at least 4 hours or overnight until thoroughly cold.
Once chilled, remove the vanilla bean seeds from the custard, then pour the mixture into your ice cream maker. Churn according to the manufacturer’s instructions, typically 20-25 minutes, until thick and creamy.
Transfer the soft ice cream into a freezer-safe container, smoothing the top with a spatula. Cover tightly and freeze for at least 4 hours, until firm and scoopable.
Before serving, let the ice cream sit at room temperature for a few minutes to soften slightly, then scoop into bowls or cones. The final texture should be velvety, with visible vanilla specks and a glossy appearance.
