MJ here do not stands for the Mary Jane you know from Spiderman but rather is called Michael Jackson as seemingly to resemble his appearance and/or the song "Black or White".
Basically this drinks is a mixture of grass jelly with soya bean. The one I had here had a history of at least 38 years and the price is consider cheap for this tall cup as they didn't increase much over the years. So anyone regardless of age can enjoy this old-school yin-yang cooling drink. The taste was balanced in term of sweetness and the grass jelly given were moderate and easy for the thin straw to suck it through. A perfect creation from the SEA region.
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🚩Soya bean & jelly drink 歡飲豆花水, Chong Pang Food Centre, Yishun Ring Rd, Blk 105, Singapore 760105