Go to custom and set the width and height to max and mines to the least. Play a few games until one tap clears the whole board except for one tile that isn't a mine (its usually obvious which one it is). Now just tap a mine to fail then restart that same board. Now you can do each match in just a few seconds just tap once to clear the board then tap a mine to fail then restart. You can also tap the screen to instantly load the board and tap to skip the mines blowing up. I got this achievement in 10-15 minutes and was the first on TA to unlock it so I'm pretty sure its the fastest way to do it plus you get progress toward 100,000 mines so I did this achievement first.