There is no such thig as a "good sauce", unless you're cooking shoes. The flavor of the meat is why you eat it not some goop spread on it. The best way to cook salmon is on an open grill. Grill it until whitened fat bubbles out between the layers, and the surface turns golden brown.
You must not have a sous vide rig. They are cheap today. Butter poached salmon with lemon and dill @ 120 for 20 minutes with the skin finished in blazing hot cast iron for 20 to 30 seconds. You will cry. I am not even going to mention how good your steaks can be or 48 hour brisket medium rare and tender as filet.
Get a sous vide rig. https://anovaculinary.com/what-is-sous-vide/