2 oz gin
1 oz simple syrup
3/4 oz fresh lime juice
3 - 4 oz soda water
2 mint sprigs
2 pieces limes

Muddle one sprig of mint with the lime pieces, lime juice, and simple syrup in the bottom of a bar glass. Add gin and shake well. Pour into a goblet over crushed ice and stir until the outer-glass frosts. Top with soda water, garnish with remaining sprig of mint, and serve.