Cut half a lime into 4 wedges and place them in a cocktail shaker.
Add 10ml of brown sugar syrup (or 2 barspoons of brown sugar) and muddle firmly until the lime releases its juice and the sugar begins to dissolve.
Add 40ml of passion fruit juice and fill the shaker with ice cubes.
Seal the shaker and shake vigorously for 10–12 seconds.
Pour the entire contents, ice and all, into a wine glass.
Top with 120ml of ginger ale and stir gently once with a bar spoon to integrate.
Garnish the rim with a fresh lime slice and serve immediately.
Muddling the lime with brown sugar rather than simple syrup adds a deeper, molasses-tinged sweetness that mirrors the raw cane sugar used in a classic caipirinha - if you can source Brazilian rapadura or turbinado sugar, the flavour payoff is worth it.
My Bar Shelf reads your shelf and shows you every cocktail you can make from what you already own, including Ipamena.