If you have the Jimmy Lightning Master Pack DLC then the first level in there is good for getting this achievement.
One of the level challenges is for finishing with 10 balls so it's pretty much set up for this by default. When I unlocked it I had 14 balls after the first shot and 2 orange pegs to clear up. I guess you need a little bit of luck but it seemed fairly easy for me.
EDIT : This was done using the new Peggle master Jimmy.