The original solution by ELITISM is great if you attempt to get this on a "lower" level.
EDIT 2 Apparently you can get this as low as level 5. Even though WithTheDawn managed to get it at this level i wouldn't plan on getting it so early on. I would never suggest not to try for blazing speed but i still would not recommend constantly trying to get it this early by letting your timer run out. It is extremely frustrating when the game decides to help you out and give you a ton of points and thrust you into the next level.
I had almost no luck with 6 for the same reason but at this point you can let your timer run down to about 1/4th or 1/5th remaining. If you let it get any lower chances are you are going to run out of time between cascades ending and you getting matches. EDIT Callum x360a has confirmed it can be had on this stage. /EDIT
Level 7 it is highly possible to get this on. Since the timer runs out on your faster you shouldn't have to worry as much about letting the timer run down.
Level 8 and above. 8 is where i just got this achievement. By the time you get to these levels if you are playing legit*** you should have to get blazing speed just to stay alive. After the first blazing speed i was about 9/10ths of the way to level 9. I waited for blazing speed to run out again. Once it did i focused entirely on staying alive and got it.
Don't think because you have to move fast this achievement is easy. I spent probably 45 minutes on this run alone. Getting that final push can be a PITA.
Best of luck!
***"cheat" listed here