Juan Collins is a cocktail made with a combination of tequila, lemon juice, club soda, and either agave nectar, sugar, or cane syrup. Essentially, it is a variation of the popular Tom Collins. In order to prepare it, tequila, lemon juice, and agave nectar (or sugar or cane syrup) are poured into a collins glass over ice, stirred, then topped with a splash of club soda.