01 - Bring 4 cups water to a rolling boil in a medium saucepan over high heat.
02 - Remove saucepan from heat, stir in dried hibiscus flowers, cover and let steep for 10 minutes to extract full flavor and color.
03 - Pour mixture through a fine-mesh strainer into a heatproof pitcher, discarding the spent flowers.
04 - Add sugar and optional honey while tea is still warm, stirring vigorously until completely dissolved.
05 - Allow tea to reach room temperature, then refrigerate for at least 1 hour until thoroughly chilled.
06 - Fill glasses with ice cubes and lime slices, pour chilled hibiscus tea over ice, and garnish with fresh mint if desired.