Follow the steps in order for the best result.
In a generously sized pot, combine the water and dried hibiscus flowers.
Bring the mixture to a rolling boil, then reduce the heat and let it simmer for approximately 2 minutes. This will allow the vibrant color and flavor of the hibiscus to infuse the water.
Remove the pot from the heat source, cover it securely, and allow the mixture to steep for a minimum of 30 minutes. This steeping process is crucial for extracting the full essence of the hibiscus.
Position a fine-mesh sieve over a large bowl or measuring pitcher. Carefully strain the hibiscus mixture, ensuring that all the liquid is collected while discarding the spent hibiscus flowers.
Add the sugar to the concentrated hibiscus tea, stirring continuously until the sugar is completely dissolved. This may take a minute or two, but ensure no granules remain.
Introduce the cold water to the sweetened hibiscus concentrate and stir thoroughly to combine. This step dilutes the concentrate to a palatable strength.
Taste the Agua de Jamaica and adjust the sweetness as desired. If it's too tart, add a bit more sugar, stirring until dissolved. If it's too sweet, add a splash more cold water.
Transfer the prepared Agua de Jamaica to a refrigerator and chill for at least 4 hours, or preferably overnight. This allows the flavors to meld and the beverage to become thoroughly refreshing.
When ready to serve, pour the chilled Agua de Jamaica into tall glasses filled with ice cubes. Garnish with a slice of lime or a sprig of mint for an extra touch of elegance.