Heat the water to 75–80°C (167–176°F), do not boil. Add the jasmine tea and steep for 2–3 minutes maximum. Remove the tea bags or strain the leaves and let the tea cool to lukewarm.
Add the lemon peel strips to the warm tea and let infuse for 5 minutes only, just until a clean citrus aroma develops. Remove the peel promptly — overinfusion turns bitter and perfumey.
Add the blackberries to a blender and blend briefly until smooth. Strain through a fine-mesh sieve into a bowl or measuring jug. Do not press the pulp. Discard solids. You want clear, inky juice — not jam.
While the tea is still warm, stir in 2 tablespoons of honey until fully dissolved. Taste and add up to 1 additional tablespoon only if needed. This drink should stay dry and floral, not sweet.
Stir 120–150 ml of the strained blackberry purée into the tea. Taste and adjust carefully — blackberry should sit under jasmine, not on top of it.
Refrigerate for 1–2 hours until fully cold and integrated.
Fill glasses with ice, pour over the chilled blackberry jasmine iced tea, and garnish with fresh blackberries and an optional twist of lemon peel.