In a cocktail shaker, combine the lemon juice, simple syrup, light rum, crème de cassis, Amaro Montenegro, and egg white.

Shake the mixture vigorously without ice to emulsify the egg white, creating a smooth and frothy texture.

Add ice to the shaker and shake until the mixture is well chilled.

Double strain the mixture using a fine mesh strainer into a rocks glass over a large ice cube, ensuring a smooth and velvety finish.

To enhance the rosemary’s aroma, gently fluff the sprig by rubbing it between your fingers, then place it atop the foam as a fragrant garnish.

Serve immediately and enjoy your Montenegro Breeze cocktail!