Quaternion Smooth Rotation

I have this code that rotates my camera and it works as intended, but I would like to make the movement smooth. How can I achieve this? I'm guessing it has something to do with Slerp?

         public float mouseSensitivity = 5.0f;
         verticalRotation -= Input.GetAxis("Mouse Y") * mouseSensitivity;
         Camera.main.transform.localRotation = Quaternion.Euler(verticalRotation, 0, 0);