2 oz of Puerto Rican Rum (or Light Rum)
1/2 oz of Maraschino liqueur (or cherry liqueur)
1/2 oz of Lime Juice
3/4 oz of grapefruit juice
1/4 oz of simple syrup
Shake and double strain into chilled coupe glass. Perfume with grapefruit puck. Garnish with grapefruit twist.