What additional ingredient is used in a Blue Margarita that distinguishes it from other variations?

A Blue Margarita is distinguished by the inclusion of blue curaçao, which is a blue-colored liqueur made from the dried peel of the laraha citrus fruit. This ingredient not only gives the cocktail its signature vibrant blue color, but it also adds a unique flavor profile that combines orange and sweetness, enhancing the overall taste of the margarita.

While Grand Marnier is a high-quality orange liqueur commonly used in margaritas, its addition doesn't specifically characterize a Blue Margarita. Similarly, strawberry mix and cassis, which is made from blackcurrants, bring different flavors and are typically used in entirely different cocktails rather than in a Blue Margarita. Hence, the key differentiating factor of the Blue Margarita is its use of blue curaçao.