Mighty Goose

I personally popped this during the first mission, but
don't worry if you don't manage to pop this achievement during your normal playthrough of the 9 missions. Once you complete the final mission, New Game Plus is unlocked as well as a secondary weapon called the Void King Glove. This Void King Glove is so OP you can burst down bosses with ease so you'll most likely get the achievement on the first boss in NG+ if you hadn't before this point.

And if that's not enough, after beating the 5 main levels of NG+ you unlock God mode with infinite ammo, infinite secondary weapon charges, infinite mighty meter and invincibility, so you'll be killing every boss expect the the final one in under 1 minute anyway if you go for S rank on all levels for that achievement.

Got this on the Aether Realms boss by using the Mighty Booster secondary but I think it's easier to go for later on the level called Kolos Prison, you have access to a tank for it so it's less dependent on what stuff you have equipped. I popped Gotta go fast also on first try by spamming the vehicle bombs with (B) and finishing him off with (X)