Finely crush the Oreo Cookies with a rolling pin between 2 sheets of wax paper and transfer to large mixing bowl.
Mix in the cream cheese and peppermint extract until well blended. Shape dough into 1 inch balls and refrigerate for 30 minutes.
Melt milk chocolate in microwave on medium power stirring often. Add in oil a little at a time until chocolate runs easily off a spoon, and is the right consistency to coat the truffles.
Dip balls in chocolate, allow excess chocolate to drain off and place on a waxed paper covered cookie sheet. Sprinkle with candy cane before chocolate sets completely.
Refrigerate for a minimum of 1 hour prior to serving.
Store in a sealed container in the fridge.