Combine the sugar, chili powder, and salt in a wide flat plastic container. Set aside.
Rub the lime wedge around the edge of the glass. Press the rim of the glass into the chili-sugar mix to coat the rim.
Combine the lime juice, passion fruit juice, and triple sec in a cocktail shaker with ice. Shake until well chilled, then carefully strain into the prepared glass. Top with the brut cava.