Using a hand mixer or a stand mixer fitted with the paddle attachment, beat the butter with the peppermint flavoring until smooth and creamy. Gradually add the powdered sugar and beat until well combined. Mix in milk, one tablespoon at a time, until desired consistency is achieved. Cover and chill in the refrigerator for 1 hour, until frosting has stiffened a bit.

Remove frosting from the refrigerator and use a tablespoon to scoop out little mounds. Arrange on a plate lined with parchment paper. Freeze mounds for 30 minutes.

Remove from the freezer and dip each mound into melted chocolate. Allow excess chocolate to drip off, then place back on parchment paper. Repeat with each mound of frosting. Allow chocolate to set before serving.