Tiffany M. Wallace is pleading guilty to ramming her pickup into a car, then throwing ranch dressing at it.
The 18-year-old entered her plea in an Iowa courtroom this week as part of a deal with prosecutors.
Wallace is to be sentenced Dec. 11 on a charge of aggravated battery.
The Idaho Statesman reports the driver of the other car told police he was cut off twice by Wallace.
He says she also threw coins and plastic containers of ranch dressing at his car.
The victim adds that Wallace rammed her truck into his car at least three times in a parking lot.