When I first started playing Evelynn I noticed there was controversy between building all ability power or a hybrid of ability power and attack damage. Even though she benefits from attack damage, her survivability is almost non-existent unless you build into it, therefore it makes little sense to get attack damage for anything other than auto attacking in the jungle or farming minions, which is a waste for this champion.

That leaves us with ability power, and of course, everyone wants to go for Rabadon's Death Cap right away but I've never felt it should be anyones first item because its unique benefit increases your ability power, thus increasing the ability power of all your other items as well -- getting it first is stupid and will greatly affect your early game.

So I offer you this build, made purely for kiting and destroying your enemy quickly. One thing to keep in mind is that after you blow your abilities, do not sit in the fight and try to rely on your auto attack to finish the job, even weak champions like Ashe will sit there toe to toe to you and kill you easily. Never pursue unless you've clearly got them on the run or you are prepared to die.