Grab any of the 7 Hoonigan cars and go to the following location:
Once there, you should be able to spot a large banana sign in front of a farm. In order to grab this achievement, you must smash the banana while in a combo and travelling at a high rate of speed. As you do, you will get the "Fruit Salad" skill in your combo and the achievement will unlock.
If you smash it and do not grab the achievement (because you were too slow or not in a combo), you can go back to the festival hub, enter and then exit and it should be respawned.