Creamy Coconut Lime Mojito

1. To make the lime sugar. Combine the lime zest, sugar, and a pinch of salt on a shallow plate. Rim your glasses in sugar, then fill with ice.
2. In a cocktail shaker or glass jar, muddle the lime, mint, and sugar (if using) together, squashing everything to release the juices. Add the white rum and coconut rum. Fill with ice and shake until combined. Add the coconut milk and shake. 
3. Strain into your prepared glass. Slowly top with ginger beer, then gently stir to combine. Enjoy immediately. 
4. Mocktail: Replace the white rum and coconut rum with 1 1/2 ounces of apple cider or apple juice.