Club soda is unconventional in margaritas, but the added sparkle elevates this drink. Look for dried hibiscus flowers in Latin markets where chiles and spices are found.Sugars 10g (est. added sugars 9g)
Combine flowers and tequila in a glass jar with a lid. Shake well. Let stand 1 hour or until tequila is strongly flavored with hibiscus. Strain over a pitcher; discard solids. Add agave, juice, and Grand Marnier. Stir to combine.
Combine sugar, cinnamon, and salt on a small plate. Lightly dampen rim of a rocks glass using lemon wedge; dip in sugar mixture to coat rim. Repeat procedure with 5 more glasses. Fill glasses with ice cubes. Divide tequila mixture evenly among glasses. Top each cocktail with about 1 1/2 ounces club soda.