Talking to an attorney friend. I say: I really appreciate how you handled my case.

[B45]

Talking to an attorney friend. I say:

I really appreciate how you handled my case. It was very professional!

 

[MikeNewYork]

That works. "The way" would also work.

 

[tedmc]

I really appreciate how you handled my case.
I really appreciate the way you handled my case.

not a teacher