For this achievement you need to complete the game under 210 minutes (3h30).
The achievement pop just before the 10 minutes credits.
I did it in 2h53 so you have a good margin.
Don't be afraid,it's easy to do if it's your 2nd run :)According to the comments,the pause menu freeze the timer.
But if you want to be sure to unlock this achievement, quit the game if you need a long break.
Here's my full walkthrough (in 2 parts) if you need a visual guide:
I'm still here to help if you need more infos
Have a good day !