Cops in Georgia are searching for this maniac who stabbed a teenage Dunkin' Donuts worker -- on video -- because the joint didn't have the flavor he wanted.
This went down over the weekend in Union City, GA where a drive-thru customer got irate the Dunkin' had run out of his favorite donut. Union City PD tells TMZ ... the guy left, but returned a short time later and went inside to start arguing with the employee.
You can see from the video, things got violent quickly ... as the suspect started flailing away with a knife ... stabbing the 17-year-old worker twice -- once in the left forearm and the upper arm.
The suspect fled before cops arrived ... bolting in a red Audi with a female passenger. Police are still looking for him, and asking for the public's help.
We're told the slashing victim was taken to a hospital for treatment and is expected to be okay.