Supersonic Gin+tonic Recipe

Make slush

Combine fresh lemon juice, fresh lime juice, and simple syrup in a small blender or cocktail mixer. Add 0.75 cups crushed ice. Blitz for 6–8 seconds until you achieve a pourable, slightly grainy slush. Taste and adjust sweetness with a few drops more syrup if needed. Keep chilled.

Chill a highball or Collins glass by filling it with ice and letting it sit for 30 seconds, then discard that ice.

Add 3 large ice cubes to the chilled glass to keep dilution slow and steady.

Pour 2 oz London dry gin over the ice.

Spoon or gently pour 1.5–2 oz of the prepared lemon-lime slush into the glass, depending on how bright and slushy you want the drink (use all if you prefer more slush).

Slowly top with 4 oz Fever-Tree Indian Tonic Water. Pour gently over the back of a bar spoon if you want a layered look; otherwise pour straight in and give a gentle stir (1–2 turns) to integrate without flattening the tonic's effervescence.

Thread the thin cucumber ribbon along the inside wall of the glass or coil it on a pick and rest it across the rim.

Float a lime wheel on top of the slush or place it on the rim.

Smack the rosemary sprig once between your palms to release oils, then place it into the glass near the rim so its aroma rises with each sip.

Serve immediately with a straw and a long-handled spoon to scoop any remaining slush. Advise the drinker to stir gently before drinking if the slush has separated.