First, make the syrup. In a saucepan, boil 3 cups of water. Then add the brown sugar. Stir continuously until sugar is dissolved. Turn off heat and let cool.
In a big pitcher, place the 1.5 liter cold water.
Add the syrup then add the chopped black Gulaman.
Place a few drops of banana extract (about 3/4 teaspoon).
Stir the drink well. Serve with ice or as is. Enjoy!
Inspired by Epicurious