Begin by placing the whole milk and chopped milk chocolate into the jar of a blender or food processor. Blend until the chocolate is finely pulverized and well integrated with the milk.

Next, add the granulated sugar, Dutch-process cocoa powder, egg yolks, fine salt, alcohol of choice, and heavy cream into the blender. Blend the mixture just until it combines; the texture may still appear slightly grainy, which is completely fine. Avoid over-blending to maintain the desired consistency.

Pour the prepared ice cream base into clean mason jars, filling only up to the base of the threading to allow for expansion during cooking. Carefully wipe the rims with a clean cloth to ensure a proper seal, then close the jars until just finger-tight.

Fill a sous vide water bath with hot tap water and gently lower the filled jars into the bath. Set the sous vide machine to 175°F and allow the water to preheat with the jars already submerged. Cook the ice cream base at 175°F for 1 hour.

After cooking, use a jar lifter to carefully remove the jars from the water bath. Place the jars on a wire rack or a heat-safe surface to cool for 30–60 minutes until they are just slightly warmer than room temperature.

To cool further, either place the jars into a refrigerator if you plan to churn later (within 24–72 hours) or prepare a rapid cooling bath. To cool quickly, set the jars in a sink, cover them with lukewarm water, and then gradually add ice to create an ice bath, maintaining the chill with additional ice as needed.

When ready to churn, operate your ice cream maker according to the manufacturer's instructions. Serve the freshly churned ice cream soft, or transfer it to an airtight container and freeze for an additional 2–3 hours to allow it to firm up for a classic scoopable texture. Enjoy each creamy, chocolate-rich bite!