Combine first 3 ingredients in container of an electric blender or food processor; top with cover, and process until powdered.
Transfer mixture to an airtight container.
Add vanilla bean.
Cover tightly, and store at least 5 days.
Remove vanilla bean before using.
To serve, spoon 1 tablespoon coffee mixture into a mug.
Add 3/4 cup hot water, and stir well.