The traditional decoration is coconut flakebut you may use sanding sugar, colored sprinkles, toasted almond slivers, powdered sugar, powdered cocoa, etc.
Instructions
Cream butter, sugar, and cocoa until smooth.
Add in coffee, vanilla and chocolate, mix well.
Add in oats and mix well on high speed with mixer until completely combined, about 3-5 minutes.
Pinch a 1 1/2 inch piece of dough and roll between your two palms.
Roll in desired decoration to coat.
Eat immediately or chill for approximately 2 hours in the refrigerator for a firmer treat.