01 - Split the vanilla bean lengthwise and scrape out the seeds. Combine the seeds, pod, whole milk, and heavy cream in a medium saucepan. Heat gently over medium-low heat until the mixture begins to steam, avoiding a full boil. Remove from heat and let steep for 15 minutes to allow the vanilla flavor to permeate the dairy.
02 - In a mixing bowl, whisk the egg yolks and granulated sugar together vigorously until the mixture turns pale yellow and reaches a thick, ribbon-like consistency.
03 - Remove the vanilla pod from the warmed cream mixture. While whisking the egg yolk mixture continuously, slowly pour the warm cream into the bowl in a thin, steady stream. This gradual addition prevents the eggs from scrambling.
04 - Return the combined mixture to the saucepan and place over low heat. Stir constantly with a wooden spoon, making sure to scrape the bottom and sides of the pan. Continue cooking until the custard thickens enough to coat the back of the spoon and registers 175°F on an instant-read thermometer. Do not allow the mixture to boil, as it will curdle.
05 - Pour the custard through a fine-mesh sieve into a clean bowl to catch any cooked egg bits or solids. Allow it to cool to room temperature, then cover and refrigerate for at least 2 hours until thoroughly chilled.
06 - Pour the chilled custard into an ice cream maker and churn according to the manufacturer's instructions until it reaches a soft-serve consistency.
07 - Transfer the softly frozen ice cream into a freezer-safe container with a tight-fitting lid. Freeze for at least 3 hours or until the ice cream is firm and scoopable.
08 - Remove the ice cream from the freezer and let it rest at room temperature for 5 to 10 minutes to soften slightly before scooping and serving.