Turning an object towards point

I'm trying to create a basic ai entity that will only move in x and z coordinates. The only thing I need it to do is to turn towards a point as well as accelerate and decelerate.

I tried this:

 Quaternion lookie = Quaternion.LookRotation(point-transform.position);
 transform.rotation = Quaternion.Slerp(transform.rotation, lookie, Time.deltaTime * turnSpeed);

And the entity turns towards the point but if it moves around the point it wont keep turning once set.

I tried getting the angle between current forward vector and target and depending on the results use transform.rotatearound but got weird results and need some help on how to proceed.