Place a strainer on top of a bowl and set it aside.
Pour the stout into a saucepan and heat over medium heat for 10 to 15 minutes until it is reduced by half. If the stove is too hot, it will boil over so watch it closely.
Add the cream, milk, 3/4 cup of sugar, and the salt to the reduced Stout. Stir until the mixture is warm then stir in the chopped chocolate and stir until melted.
In a separate bowl beat the yolks with the remaining 1/4 cup sugar.
Whisk a cup of the chocolate stout mixture into the yolk mixture. Continue whisking until well combined then pour it into the saucepan with the rest of the warm chocolate stout.
Stir the mixture constantly while you heat it over medium heat. Continue heating and stirring until an instant-read thermometer reads 180°-185°F. (make sure the mixture does not boil).
Pour the custard into the strainer that is set over a bowl to remove any bits of cooked egg yolk.
Stir in the vanilla and salt then cover the mixture and place it in the fridge to chill.
Ice cream machine:
Pour the chocolate custard into an ice cream maker and follow the manufactures instructions for churning ice cream
Video
Notes
Flavor note: Reducing the stout concentrates its malty flavor without overpowering the chocolate. It adds depth and richness, with just a subtle hint of stout in the background.Reduce gently: Let the stout simmer, not boil, to avoid overflow and build flavor without bitterness.Temper the egg yolks: Slowly whisk hot cream into the yolks to prevent scrambling. This keeps the custard smooth and the final ice cream lump-free.Use a thermometer: Heat the custard to 180–185°F—just enough to thicken it without curdling the eggs. This is the range where the yolks set and give the ice cream its silky texture.Strain for smoothness: Even well-tempered custard can have tiny clumps. Straining removes them before they make it into the ice cream maker.Chill before churning: Let the custard base chill completely before churning. A cold base freezes faster, which means smaller ice crystals and a creamier texture.