Posted 11 June 2007 - 05:22 AM
Okay. You are right to hit the nail on the core of the topic, which btw is no longer chicken (or only marginally so) but truffles. All the more since the book is now decidedly out of print, I may as well recall the main points here.
Truffles are not just a fungus. They are an aromatic agent whose field of action is very particular, going far beyond mushroomity. At early periods of truffle studies (early 19th century) it was even wondered whether they were vegetable, animal or mineral. Some wrote they were a little of the three. One biologist believed he got rid of the problem by describing them as "animalized vegetables". The truffle is very paradoxal. There is some sort of historical rule concerning the use of black truffle: the more pungent and spicy the diet is, the less truffles are used. When spices and fermented foods go down, truffle goes up. One part of the truffle paradox is that, although its flavor is strong, it may be easily destroyed by other assertive flavors. It is actually very fragile and is better off used with plain, mild ingredients, which it will support and reveal. Also, it is unlikely to overpower the flavors of other foods. As Pébeyre writes, "elle doit avoir un peu de vide autour d'elle", i.e. it should be allowed to perform in a blank space, and not be challenged. Hence its uses with mild fowls, foie gras, pâtés, potatoes, rice, cream, etc. Some strong flavors suit it well (garlic for instance) some do not. To illustrate that, it is interesting to notice that there is no traditional use of truffles in Provençal cooking or in Spanish cooking, although they are plentiful in upper Provence and eastern Spain. Whereas they are important in French Southwestern and Lyonnais cuisines: a quick study of those cuisines and their favorite ingredients will tell a lot.
Morels (tastewise) are actually closer to truffles than other mushrooms in the way that they accompany tastes without overpowering them, hence their traditional use with mild-flavored ingredients like first-rate chicken, fish, veal, cream, etc. Trumpets, as mushrooms go, and however much we may like them, are not so versatile and I'd even say they are at the bottom of the fungus scale regarding versatility. They do not really support and bring out flavors, they add something different, as do for instance cultivated mushrooms that are open and a bit on the old side. There is such a difference of nature between truffles and trumpets that you cannot put them in the same category.
Take for instance a gamey bird like a guinea-fowl. I'd easily prepare it with trumpets provided that they are fresh enough, but I would rather use a truffle on a milder bird. Not that I think a guinea-fowl with truffles would not be good. But I think the truffle would interact better with good chicken.