Use a sharp knife to carefully slice the vanilla beans lengthwise, then scrape out the tiny seeds into a bowl to release their fragrant aroma.
In a saucepan, combine the heavy cream, whole milk, and vanilla seeds along with the pods, then heat gently over medium until just steaming, about 5 minutes. Do not boil.
While the cream heats, whisk together the egg yolks and sugar until the mixture is pale and slightly thickened, about 2 minutes.
Slowly pour a ladle of the warm cream into the egg mixture, whisking constantly to temper the eggs and prevent curdling.
Return the egg mixture to the saucepan with the remaining cream, then cook over low heat, stirring constantly, until the custard thickens enough to coat the back of a spoon, about 5 minutes.
Remove the custard from heat, discard the vanilla pods, and pour the mixture through a fine sieve into a clean bowl to remove any cooked egg bits.
Stir in the vanilla seeds from the scraped beans, then place the bowl into an ice bath to cool rapidly, stirring occasionally until the mixture reaches room temperature.
Cover the custard and refrigerate for at least 4 hours or overnight to let the flavors meld and the mixture chill thoroughly.
Once chilled, pour the custard into your ice cream maker and churn according to the manufacturer’s instructions until it reaches a soft, creamy consistency.
Transfer the churned ice cream to a freezer-safe container, smooth the surface, and cover tightly.
Freeze for at least 4 hours or until firm, then serve scooped into bowls to enjoy the velvety vanilla speckled with tiny seeds.
