01 - Place vanilla ice cream, milk, peppermint extract, fresh mint leaves if using, and sugar in blender.
02 - Blend on high speed until completely smooth and creamy, about 30-60 seconds.
03 - Taste and adjust sweetness or mint intensity by adding more sugar or extract as needed.
04 - Pour mixture into two chilled glasses, dividing evenly.
05 - Top each glass with a generous swirl of whipped cream.
06 - Place a maraschino cherry on top of each milkshake and serve immediately with straws.