Forza Motorsport 6: Apex

From the main menu:

Free Play
Select Track > Top Gear > East Circuit (Day)
Select Car > 2017 Ford GT
Game Options > Max Drivatars - 15, Drivatar Difficulty - New Racer, Limit Drivatar Aggression - On, Laps - 2, Collision Mode - Always Off
Assists - Do whatever you're comfortable with, but change braking to at least 'ABS on' so it doesn't slow you down when coming to a corner

Start the race and go full throttle until you see the red braking line. You can go ham into the turns and break a bit past where it turns red but keep the wheel straight. Cut the corners tight and slam the throttle again. May take some trial and error but you will get the hang of it. Two laps because I was not able to catch up to the first car fast enough on the first lap.

EDIT: This setup appears to be bugged at the moment. No matter what you choose for Drivatar settings, no cars will show up on the track but your own. I recommend posting on the official forum to report this bug if you aren't able to get it to work.

http://forums.forzamotorsport.net/turn10_topics86_Forza-Moto...

Go to free race and then select the third top track as it's the shortest. The make sure the max drivatars is on and for the car choose the 2017 Ford GT and then simply win the race.

From what I've read the achievement sounds a bit glitchy so if it doesn't unlock, try again a few times and then it should unlock! :)