Bring the water to boil in a small pot. Add the torn mint leaves and give the pot a stir. Allow it to cool.
Add the blackberries to a blender. Place a strainer over the mouth of the blender and pour the mint and water mixture into the container.
Discard the mint leaves. Blend the liquid and the blackberries on low speed for just a few seconds at a time, just enough to break the berries apart but not enough to puree them. Fill a juice pitcher halfway with ice and add the mint sprigs.
Pour the lemonade and the blackberry mixture over the ice, add Stevia to taste. Stir the blackberry mint lemonade and add more ice if necessary before serving.
3 cups of water
18 mint leaves (torn)
2 cups blackberries (frozen/fresh)
3 mint sprigs
4 cups prepared lemonade
Stevia to taste