Rub the cut side of the grapefruit wedge around the lip of a highball or Collins glass. Spread the lava salt on a small plate and gently press the wet rim into the salt to coat about half to three-quarters of the rim. Set the glass aside and place a large ice cube or two into it.

Build & Shake

Combine base ingredients

In a cocktail shaker, add 2 oz mezcal, 0.5 oz Campari, 0.5 oz The Woods amaro, 2 oz fresh pink grapefruit juice, 0.5 oz fresh lime juice, and 0.5 oz agave syrup.

Add ice and shake

Fill the shaker with ice and shake vigorously for 10–12 seconds until well chilled and slightly diluted.

Finish & Serve

Strain and top

Double-strain the shaken mixture into the prepared ice-filled glass. Top gently with 2 oz chilled soda water to maintain effervescence and lightness.

Bitters and garnish

Add 2 dashes of Mt. Fuji bitters on the top of the drink. Express the grapefruit wedge over the drink to release oils, then drop it in as a garnish along with the sprig of thyme or rosemary. If you prefer a smokier salt presence, very lightly sprinkle a tiny pinch (up to 1/8 tsp) of extra lava salt on the exposed surface of the drink; be careful not to oversalt.

Final touch

Give the drink a short gentle stir (1–2 turns) to integrate the bitters and soda without losing carbonation. Serve immediately.