Target rotation positioning issue (Find look at rotation node)

[ClockworkOcean]

This crops up a lot

How to get the angle between a world location point and where a pawn is looking?

When the pawn reaches a certain point I want to rotate it using AddActorWorldRotation until it is facing the StartingLocation which is the place where it was placed the first time, stored as a vector, but for that, I need to know the angle between the forward vector and the StartingLocation. How do I do that?