Split the vanilla bean lengthwise and scrape out the tiny black seeds with the back of a knife. Combine the seeds and pod with the milk and cream in a saucepan. Bring to a gentle simmer over medium heat, just until bubbles appear around the edges, filling your kitchen with that sweet vanilla aroma.
While the custard heats, whisk together the egg yolks, sugar, and a pinch of salt in a bowl until well combined and slightly pale. This creates a smooth, creamy base for the custard.
Slowly pour a ladle of the hot milk mixture into the egg yolks, whisking constantly to temper the eggs and prevent curdling. Repeat this process until you've incorporated about half of the hot liquid.
Pour the tempered egg mixture back into the saucepan with the remaining milk and cream. Cook over low heat, stirring constantly with a whisk, until the custard thickens enough to coat the back of a spoon. This should take about 8-10 minutes and the mixture will be slightly steaming but not boiling.
Pour the custard through a fine-mesh sieve into a clean bowl to remove the vanilla pod and any cooked egg bits. Place the bowl in an ice bath and stir occasionally to cool the custard quickly, helping it set and preventing overcooking.
Once the custard is thoroughly chilled, give it a good stir and then transfer to your freezer-safe container. Cover tightly and freeze for at least 4 hours, stirring every 30 minutes during the first 2 hours to break up ice crystals and develop a smooth texture.
After the ice cream has frozen to a soft but scoopable consistency, let it sit at room temperature for 5-10 minutes before serving. The vanilla aroma will intensify, and it will be perfectly creamy and speckled with vanilla seeds.
