Add 45ml gin, 5ml grenadine, and 5ml powdered sugar to a mixing glass filled with ice.
Stir well for 15–20 seconds until the sugar is fully dissolved and the mixture is well chilled.
Strain into a highball glass filled with fresh ice cubes.
Top with 90ml chilled carbonated water and give one gentle stir to integrate.
Garnish with a skewer of fresh pineapple chunks and whole strawberries. Serve immediately.
Stirring rather than shaking preserves the carbonated water's fizz - always add the soda last and stir just once or twice to keep maximum effervescence in the glass.
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