"The recipe calls for either food-grade peppermint essential oil or mint extract. In either case, you'll want to add more of either if needed - so taste the filling before rolling, cutting and dipping. I used about 1/4 teaspoon peppermint oil initially but ended up adding a few more drops for a more potent peppermint taste. I haven't tried this yet but I think it would be absolutely delightful to add a touch of peppermint to the chocolate, too...."