Whisk the heavy cream, vanilla, and malt powder in a lathe bowl and set aside.
In another large bowl, whisk the egg yolks until pale yellow.
In a saucepan, warm the half-and-half with the sugar and salt until just steaming (tiny bubbles will form around the edges). While continuously whisking, slowly pour the warm half-and-half mixture into the bowl with the egg yolks. Transfer the egg mixture back into the saucepan and cook over medium heat, stirring constantly, until the mixture thickens and can coat the back of a spoon.
Remove from heat and pour the egg custard through a strainer, whisking into the heavy cream mixture. Lastly, whisk n the bourbon.
Bring the temperature down by continuing to whisk the bowl in an ice bath before covering and allowing to cool completely in the refrigerator.
When completely cool, churn the ice cream according to the manufacturers directions on your ice cream maker. When set, fold in the chopped malted milk candies.