In a mixing glass or shaker, add fresh blueberries, fresh mint leaves, simple syrup, and lemon juice. Gently muddle 8–10 times until blueberries break and mint releases aroma—avoid over-muddling the mint to prevent bitterness.

Add the gin and elderflower liqueur to the muddled mixture. Fill the shaker with ice and shake vigorously for 12–15 seconds to chill and dilute slightly. Double-strain into a chilled Collins or highball glass filled with fresh ice to remove solids and seeds.

Mint Foam (Aromatic Top)

Prepare mint-infused water (can be done ahead)

To make mint-infused water: steep 1 cup of fresh mint leaves in 1 cup of just-boiled water for 5 minutes, cool and strain. Measure 0.5 oz for the foam. (If using aquafaba, skip infusion but keep vanilla syrup and bitters.)

Dry shake foam

In a separate shaker, combine egg white (or aquafaba), mint-infused water, vanilla syrup, and citrus bitters. Dry shake (no ice) vigorously for 20–30 seconds until foamy and frothy.

Wet shake and finish

Add ice to the foam shaker and shake again for 10–12 seconds to chill and stabilize the foam. Fine-strain the foam gently over the top of the strained cocktail in the glass to create a soft aromatic head.

Fizz & Garnish

Top the cocktail gently with 2 oz chilled club soda to give a light fizz. Pour slowly so the foam remains prominent.

Skewer 2–3 blueberries on a short pick and lay across the glass, or float them on the foam. Add a small mint sprig and an edible flower petal on the foam for an aromatic floral presentation. Serve immediately.