Beat egg white and cream of tartar with a mixer at high speed until soft peaks form. Gradually add sugar, vanilla, cocoa, and coffee powder.
Drop mixture onto foil lined baking sheet in 12 mounds. They should be about 2 inches apart.
Bake 40 minutes at 250 degrees F (120 degrees C), or until firm. Turn off oven, and let meringues cool in oven for 1 hour. Do not open oven door while the cookies are cooling.