In this video guide I will show you how to deflect an enemy with their own slowed blaster bolt. In order to get this achievement you will first need to wait until you get force pull. This will be story related so don't worry about missing it.
Once you have force pull you can now attempt this achievement. You will be on the planet Zeffo
when getting force pull. Just go find a stormtrooper and wait for him to shoot at you. Once he does, hit him with a slow with the RB button and then press LT to force pull him into the blaster bolt. If done correctly he should die in one hit and the achievement will pop.