--Make sugar syrup: in a small saucepan, combine water and sugar; over medium heat, cook until sugar is dissolved and liquid is clear--approx. 5 min. Let cool completely.

--Into a sterile quart jar with tight fitting lid, pour vodka, sugar syrup, and peppermint oil or extract. Stir well. Store in cool, dark place, allowing it to steep for 2 weeks. Turn jar upside down every 2-3 days to mix, or remove lid and stir. Transfer to smaller sterile bottles, if desired.

NOTE: For a sweeter, thicker liqueur, add more sugar syrup.