2 ounces light rum (also called white rum), or rhum agricole

2 ounces dark rum, or Jamaican rum

2 ounces fresh lime juice

1 ounce orange curaçao (like Grand Marnier) or, if you prefer, a triple sec (like Cointreau)

1 ounce orgeat syrup

½ ounce simple syrup

Fresh mint and/or lime for garnish

Fill a cocktail shaker about halfway with crushed ice.

Add the rum, lime juice, orange liqueur, orgeat, and simple syrup. Cover, and shake well, about 30 seconds.

Pour equally into two old-fashioned glasses; top with more crushed ice as needed. Garnish with mint springs and lime, and serve.