Fresh pineapple wedges and leaves,to garnish (optional)
Combine rum, pineapple juice, lime juice, Campari, and simple syrup in a cocktail shaker with 2-3 ice cubes. Shake until nice and frosty. Pour into two champagne flutes or coupe glasses and top each with 1-2 ounces of ginger beer. Garnish with pineapple wedges and leaves. Serve chilled and sparkling.