Add the milk, half-and-half, sugar, cornstarch, and salt to a sauce pot over medium heat.
Cook the ice cream base, whisking constantly, for 10 minutes, or until slightly thickened. Remove from heat.
In a mixing bowl, quickly whisk 1 large ladle of the hot ice cream base into the beaten egg yolks, whisking until smooth and combined.
Whisk the egg yolk mixture into the pot with the remainder of the ice cream base.
Add the vanilla extract and vanilla bean seeds to the ice cream base, and stir until the seeds are incorporated throughout. Let cool to room temperature before refrigerating until ice cold, at least 8 hours.
Churn the ice cream base, and chill according to the manufacturer’s instructions for your brand of ice cream maker.