Just a few thoughts:
Note to Nicko: I used the links Shel provided (h/t Shel!) and did a tiny bit more follow up. The recipe was plagiarized from The Cook's Decameron (Recipe 70, there), and it's posting is not in accordance with the rules Chef Talk as I understand them. Furthermore, given the character of the "writing," which is at least distinctive enough to seem quaint, under other circumstances it might have been a copyright violation. But it is not, as The Cook's Decameron is public domain, online as part of the Gutenberg Project, and there's nothing here for you to worry about.
The Cook's Decameron: From a food perspective, everything has a sort of English upper class tempered by French accent to it. The NY Times gave it passing notice in 1901 and seemed to find it "authentic." [ahem]. The author, W.G. Waters was largely as she portrayed herself, and a luminary of the London Women Writers Club.
The setup is a series of ten dinner parties given by an upper class English couple living in Italy during the late Victorian period. The guests are of a variety of different nationalities, although the British -- particularly the English -- are overrepresented. The class spectrum runs the gamut from upper middle to middle upper. From A- to B+ as we might say now -- if we were feeling nasty. The hostess/author and many of the guests are period foodies, so the conversation often revolves around food with just enough on other subjects for the author to have fooled herself into believing she'd provided verisimilitude. Food is discussed, recipes are shared, hilarity ensues. But alas, not much. The recipes are neither regional, authentic, nor good. They've been de-garlicked for the benefit of British palates, and have plenty of French-staff-in-the-kitchen variations. I'm not sure whether or not these dinners actually took place as chronicled, were mere literary device, or some combination. On the part of guests now long dead, I vote device.
The book absolutely does convey a portrait of wealthy, self-approving people, who believe they are the first to have discovered that eating is fun. Elizabeth David it ain't. The book is in the public domain and available for free download.
Salmone alla Francesca: I agree with everyone else, it looks just terrible. Why was this posted?
In addition to the overcooking and other flaws there's the problem of the espagnole suggestion.
Just to get us all on the same sauce espagnole page: Saute a mirepoix in butter until well sweated; add some more butter and enough flour to form a roux; cook the roux until just browned (peanut butter); push the roux to one side of the pan and add a bit of tomato paste; cook the paste until it starts to brown, then stir it and the roux together; cook until the paste is completely darkened, and add some stock, a few sprigs of parsley and some bay leaf; reduce by 25% until consistency is light to medium nappe; sieve; reserve. Espagnole is a mother used for five or six daughters, including demi-glace, and hundreds of derivatives. FWIW, the "brown" part of espagnole's other name, "brown sauce," comes not from the color of the stock, but from the combination of browned roux and tomato.
From a technical perspective, espagnoles are a little more flexible than most recipe sources would have you believe. They can be made with light poultry stocks, vegetable stocks, or even with water. I've never made one with a fumet, and imagine it would be very difficult to take the fumet down by a 25% reduction without ending up with something pretty awful. If you put a gun to my head, and ordered a fish espagnole, I'd start by making espagnole with a court bullion, but before sieving, add a little clam juice (clam juice is cheap, stands pretty well for strong fish stock, unlike fish stock can take a heck of a pounding, and has saved many a saucier's derriere), some shrimp or lobster shells, and gently simmering until the flavor was extracted -- 10 minutes-ish -- and then the inevitable sieving. (You know, with the right additions, you'd have a pretty good creole or etouffe going. Hmmmm.
That said, an espagnole of any sort is not particularly good on its own -- it's usually a first step on the way to something else. Consequently, you don't often see it added to dishes late in the game, as in this case to "moisten." Also, even if by some miracle the combination tasted good, the addition of espagnole would destroy the appearance.
Espagnole is something upper crust English kitchens might have in the ice box -- after Escoffier was translated into English in the mid twenties and after they had ice boxes. It wasn't something even the best homes had hanging around in the larder at the turn of the century -- which makes W.G. Waters a pretty darn adventurous cook (or at least the employer of a pretty darn adventurous cook). Props where props are due. You go, girl!
Note to cookcook: Welcome to the forum. I'm looking forward to reading your own recipes, about your own experiences, answering your questions when I can, and hope you're not offended or frightened off by the reaction to your post. I'd very much like to know what were you thinking when you posted this recipe. It certainly has a discussion going.
BDL