If you have a smoking gun or grill with a smoker box, lay the pineapple chunks on a tray and lightly cold-smoke them for 6–8 minutes until they pick up a gentle smoke aroma and light surface color. If no smoker is available, briefly torch the pineapple surface or char on a hot pan for 1–2 minutes per side to impart a faint caramelized/smoky note.

Combine the smoked (or charred) pineapple chunks, sugar, and water in a medium saucepan over medium heat. Split the vanilla bean and scrape the seeds into the pan; add the pod as well (or add 1 tsp vanilla extract after removing from heat). Stir to dissolve the sugar.

Bring the mixture to a gentle simmer, then reduce heat to low and simmer uncovered for 12–15 minutes, mashing the pineapple occasionally with a spoon to release juice and flavor. The syrup should become slightly thickened and richly aromatic.

Remove the pan from heat. Add the gentian root (or 1 tablespoon gentian infusion concentrate) to the hot syrup and steep for 5 minutes to extract a subtle bitter-floral note. Taste after 3–5 minutes — gentian is potent, so do not over-steep.

Strain the syrup through a fine-mesh sieve or cheesecloth into a jar or bowl, pressing on solids to extract as much liquid as possible. Discard solids (or reserve pineapple for another use). If using a vanilla bean pod, remove and discard it. Stir in smoked salt (about 1 tsp) if you want a slight savory-smoke accent; adjust to taste.

Cool the syrup to room temperature, then refrigerate until cold. The flavored syrup will keep in the refrigerator for up to 7 days.

Cocteau Lemonade Assembly

Fill a highball or Collins glass with ice (about 1 cup).

Pour 3 oz fresh lemon juice over the ice. If you prefer a sweeter balance, start with 2.5–3 oz and adjust to taste.

Add 3 oz of the chilled smoked pineapple-vanilla syrup. Stir gently to combine lemon juice and syrup.

Top the mixture with 6 oz chilled light tonic water. Stir once gently to incorporate but preserve carbonation.

Garnish with an edible gentian flower or a thin gentian twist for aroma, and a lightly torched or smoked pineapple wedge on the rim. If you used smoked salt in the syrup, optionally rim half the glass with a tiny amount for extra balance.

Serve immediately. Taste and adjust: if the drink is too bitter from gentian, add a splash more syrup; if too sweet, add a touch more lemon juice; if lacking freshness, add a spritz of soda water.