How to Make It
Prepare the mix: Add pineapple juice and granulated sugar to a 16-oz. glass bottle with a tight-fitting lid. Cover with lid; shake vigorously until sugar dissolves, 1 minute. Add orange liqueur (such as Cointreau or Grand Marnier) and fresh lime juice. Cover with lid; shake until well combined. This mix can be refrigerated up to 3 days; shake before serving.
Prepare the Lime Sea Salt: Line a rimmed baking sheet with parchment paper. Spread fresh lime zest across prepared baking sheet. Bake at 150°F (or lowest temperature) until zest is fragrant and dry but not browned, 10 minutes. Remove from oven; cool on baking sheet set on a wire rack. Combine coarse sea salt and cooled zest. Store in an airtight container up to 6 months.