Mix the sugar and vanilla bean in a bowl; set aside about 30 minutes.
Preheat a cotton-candy machine according to the manufacturer's instructions, at least 5 minutes. Turn off the cotton-candy machine, pour the sugar mixture into the center and turn on the machine. When it starts to spin cotton candy, hold a paper cone in the middle, perpendicular to the machine, and move it around the edges to accumulate the cotton candy on the cone. Sprinkle with the curry powder.