Step 1: Take a sturdy glass and add mint leaves, sugar, and lime juice into it – muddle it at the bottom of the glass to release the mint’s essential oils until the sugar is fully dissolved.
Step 2: Pour rum into the glass and stir it well to combine everything – you can also use a cocktail shaker but don’t shake as rigorously.
Step 3: Add a splash of cranberry juice for a festive color, and adjust based on how tart or sweet you want the cocktail to be.
Step 4: Fill the glass with crushed ice, but leave some space on the top for soda – then top off the drink with club soda and give it a gentle stir.
Step 5: Finally, garnish your cocktail with fresh cranberries, a slice of lime, and a rosemary sprig to really give it a Christmas theme.