Run the lime wedge around the rim of a chilled coupe or rocks glass. Mix the smoked sea salt and fine sugar on a small plate, then dip the wet rim into the salt-sugar mixture to coat evenly. Set the glass aside in the freezer for a minute while you make the cocktail.

Dry shake (if using egg white)

In a cocktail shaker add the tequila, ancho chile liqueur, fresh lime juice, agave syrup, passion fruit purée, orange curaçao, and the egg white (if using). Seal the shaker and shake vigorously without ice for 12–15 seconds to emulsify and create a silky foam.

Wet shake and chill

Open the shaker and add a generous handful of ice (or about 1 cup). Shake again vigorously for 12–15 seconds until the shaker is cold to the touch and the mixture is well chilled and aerated.

Strain and serve

Double-strain the cocktail into the prepared chilled coupe or over fresh ice in the prepared rocks glass using a fine-mesh strainer to remove ice shards and any large pulp. This ensures a smooth texture, especially if you used passion fruit purée.

Garnish

Float 2 dashes of Angostura bitters on the foam or on the surface of the drink. If desired, use a toothpick to create a simple pattern by dragging the bitters through the foam for an attractive finish. Add the used lime wedge or a small wheel of lime on the rim as garnish.

Serve

Serve immediately. The cocktail yields one well-balanced serving with smoky-sweet chile notes, bright passion fruit and lime, and a slightly sweet salted rim for contrast.