The base for bouillabaisse: assorted rock fish at the famous crieé (morning fisherman's market) on the Quai des Belges in Marseille.
Actually, ya gotta have what the French call "soup" fish: a mix of bony, ugly, strongly flavored specimens too small to be eaten for their flesh, vive (weever) congre (local conger eel), girelle and galinette and roucau (all varieties of wrasse), crénilabre-paon ("peacock" wrasse), labre varié(more wrasse), grondins (sea robin), rouquié (red mullet), merle (whiting), rascasses (scorpion fish), petits sars (sea bream), and so on. You get the picture: what we might charitably call "by-catch." But that's just for saffron-scented the soup, which thickens naturally (all those gelatinous fish bones, all that dissolved fishiness), which develops a rich ochre color as it simmers.
The fish themselves are then removed from the soup, which is served to the diners accompanied by croutons (slices of toasted baguette, not cubes out of a box) onto which you slather a spicy, garlic and red-pepper mayonnaise called rouille (literally, rust-colored). Top that with shredded cheese if you're so inclined; personally, I find that the cheese gets in the way of the soup's quintessential fishiness.
Then comes the main course, first presented to the diners in the round before cooking, and again afterwards, prior to being de-boned tableside by the waiter: white scorpion fish, red mullet and sea bream (in other words, your socially presentable seafood). You can also add a lobster-like Cigale de Mer, or, should it be handy, an actual spiny lobster. If you're doing this right (and why the hell wouldn't you be doing it right, since it's so much trouble in the first place), tradition says you need at least four of these fish.
The notion of a fisherman's stew is nothing new, and varies around the world. It exists in Italy as brodetto, cacciucco and, in the Ligurian dialect of Genoa, as ciuppin. (San Francisco's Genovese fishermen this called it Cioppino.) A proper Bouillabaisse, with dozens of cheaper fish going into the broth and a splendid display of expensive specimens for the main course, is no less costly than a juicy rib-eye at a steak-house, about 50 euros per person these days, almost always requiring at least two orders and a full day of notice so the restaurant can acquire the fresh ingredients.
There's a "Bouillabaisse Charter" signed by a dozen or so restaurants in Marseille and Provence, which commits them to a set of rules that includes the requirement to debone the fish in front of the customer, tableside, but--recognizing the seasonality and variability of the catch--refrains from identifying specific fish varieties for the soup or for the main course. (One spot, the Miramar in Marseille, actually owns the website www.bouillabaisse.com.) Stylistic differences abound. Loury, a restaurant in Marseille, where I had bouillabaisse in 2006, ladled more soup over the filleted fish; Le Grand Large, here in Cassis, served the fillets with a boiled potato and a lemon.
Six long years I've waited for another authentic bouillabaisse. I'm not sure Le Grand Large deserves being called "authentic," since it only had the one "main" fish (sea bream), but I'm not complaining. Au contraire, my heartfelt thanks to the regional tourist board for Provence, which hosted an entire week of travel-industry workshops, meetings, meals and tastings.
Le Grand Large, Esplanade Charles de Gaulle, 13260 Cassis, France, 04 42 01 81 00