Split the vanilla beans in half, careful not to scrape the seeds. Put the beans in a mason jar and cover with bourbon. Close the jar tightly and shake. Wait at least 24 hours to use.
Sift the baking cocoa and the milk powder into a small bowl. Put the vanilla ice cream, baking cocoa/milk powder, Kahlua and 1 ounce bourbon in a blender. Blend until smooth. Pour into glasses.