How to Make It
Add a large ice cube to two rocks glasses and set aside.
In a cocktail shaker, muddle the blueberries, mint and Simple Syrup until well pulverized. Add the rum, lime juice and bitters to the shaker. Add a couple handfuls of ice to the shaker, cover, and shake vigorously for 15-20 seconds.
Strain the cocktail, allowing some of the mint and blueberry pieces to flow through, into the prepared glasses.