None. There are no foods that lower blood sugar quickly.
There are some supplements which MAY work, but they do NOT work quickly. Cinnamon, Ginseng, Chromium supplement, Probiotics, Aloe Vera, Berberine, Vitamin D, Gymnema, Magnesium, all claim to help, but there is scant evidence that supports that these will work for all people.
Sadly, it seems that some idiot that THINKS they know better, is offering thumbs down again. I pity that person's lack of intelligence and/or understanding of blood sugar (glucose) control.