Strain into a jar or glass container using a fine mesh strainer and add sweetener to taste. I found 1/3 cup (amount as original recipe is written // adjust if altering batch size) was about the right amount, using half agave nectar, half cane sugar. Stir to dissolve and let cool.
To make two margaritas, add ice, cooled hibiscus tea concentrate, lime juice, tequila and 1 Tbsp agave nectar (optional // amount as original recipe is written // adjust if altering batch size) to a cocktail shaker and shake vigorously to combine.
*Nutrition information is a rough estimate calculated with the optional agave nectar.
*Hibiscus tea concentrate adapted from Bon Appétit