You won a round of a career event without using the brakes.

There are various ways to do this achievement, but I recommend doing it during WSR Season 1, Motor Mavens Faceoff Series, using any car. You can choose any difficulty, although Normal isn't too hard for this achievement.

Just take your time around the track, not using your brake. Pull off the throttle to slow down, and rub against walls in order to slow down faster when you need it. Use the throttle around the corners to start a drift, making it easier to corner.

Just make sure to win the race, and you will unlock the achievement