1 cup sugar
1 cup water
1 bunch of fresh mint, about 1 1/2 tightly packed cups, washed and divided
6 (1/2-inch) slices of grilled pineapple, cored and cut into 1-inch pieces (see Recipe Note)
1 cup freshly squeezed lime juice
2 1/2 cups light rum
1 liter club soda, chilled
In a small saucepan, combine the sugar, water and half the mint. Simmer over medium high heat just until the sugar is dissolved. Strain and chill.
In a large pitcher, combine most of the pineapple, the rest of the mint and a splash of the lime juice. (Reserve 6 to 8 pieces of pineapple for garnish.) Muddle to release the aromas of the mint and smash the pineapple. Add the simple syrup, the rest of the lime juice, the rum and club soda and stir.
Pour into 6 to 8 ice-filled glasses and garnish each with a piece of grilled pineapple.