How do I transition smoothly between two lerps/slerps?

How do I smoothly transition from one lerp/slerp to another while the first is still in progress? Currently the code just stops the object rotation before starting the second.

The code so far:

            if (rotating)
            {
                rotationTime += Time.deltaTime * RotationSpeed;

                myRigidBody.transform.rotation = Quaternion.Lerp(myRigidBody.transform.rotation, DesiredDirectionOfTravel, rotationTime);
            }

            if (rotationTime >= 1.0f)
            {
                rotating = false;
            }

If you want multiple rotations you could use Quaternion.LerpUnclamped. Or replace rotating = false; with rotationTime = 0f;