Another idea:
Play the chord. Decide which note you want to bring out. Play it first, then play the rest of the chord.
Play the rest of the chord, without the note, then play the note. One way usually works better than the other.
Gradually bring the two closer an closer. When you can no longer hear a diffence between when the notes are struck, you are on the right track.
If you listen very carefully, notes that are brought out are struck a bit early or a bit late, but the difference is often so small that it is either inaudible or you can't hear it until you listen for it. This is why even great players often "split the hands" a bit when they are making a bit difference between the balance of the hands. Again, sometimes it is obvious if you listen for it, but other times not.
Gary