Thinking evil has its roots on ignorance is like being an ostrich covering their head from the sun. Evil is not about ignorance, you can be very aware of the fact that you are evil and enjoy that, there are quite concrete examples of people who have done so before, so that hypothesis doesn't really match with a concrete reality. Evil for the sake of it does exists, and since it is committed for the sake of itself, it requires awareness, therefore leaving ignorance out of the question.
Also, what we think as evil is mostly what is destructive or unethical, yet also these two doesn't always meet at the same point and even when something is both destructive and unethical, it could still be just and fair both hypothetically and realistically, I think, (yet the examples are based on the assumption of a widely accepted or followed moral compass)
If so, regarding these perimeters, what makes evil?
Destructive and unethical acts that regarding a conscious "good" value? Mm, this can be a real stumper.