In a large saucepan, combine stout, cream and milk; bring to a simmer. In a bowl, whisk the egg yolks with the sugar. Gradually add the hot stout mixture to the yolks, whisking constantly until well blended. ADD VANILLA EXTRACT NOW? Pour the mixture into the saucepan and cook over moderate heat, stirring constantly until it coats the back of a spoon, about 5-7 minutes (don’t allow it to boil). Pour into a medium bowl set in a large bowl filled with ice water. Stir until the mixture is cold. Pour into an ice cream maker and proceed according to the manufacturer’s instructions. Be careful not to fill the maker more than halfway per batch. Pour soft ice cream into a container, seal and freeze until firm. Serves 6.