When I was young, this old French classic was still - though in a quiet way - very much in vogue. I dare say it was because the novelty of using so many garlic cloves had not worn off; it seemed somehow dangerously excessive. Even so, I don't think anyone would think it quite unremarkable now to put 40 cloves of garlic in a casserole. Certainly, if you peeled and chopped - let alone minced - the garlic, it would be inedible, but garlic cloves cooked encased in their skins grow sweet and caramelly as they cook, like savory bonbons in their sticky wrappers, rather than breathing out acrid heat. This is a cozy supper, not a caustic one.
This dish entered my canon under someone else's auspices. A few years ago, for the fortieth birthday of a then-colleague and friend of mine, Nick Thorogood, his partner asked everyone to contribute something written expressly for purpose to be compiled in a fat tribute of a book. Since most of Nick's and my conversation dwells, with almost fetid passion, on food, it seemed only proper to write a recipe for him. And given that it was his fortieth birthday, this seemed the right recipe.
It is not quite the classic version (not that there is only one: food is as variable as the people who cook it) but it sticks to the basic principles. Maybe because the white meat on chicken tends towards the utterly tasteless these days, I prefer to use not a whole chicken, but thigh portions only. Naturally, this wouldn't make sense if you were raising your own chickens, then slaughtering them for the pot, as was the custom when this recipe came into being (and very good it would have been, too, for adding oomph to an old bird) but if you're following the contemporary shopping model, it works very well. For some reason, I veer towards recipes that can easily be cooked in one of my wide and shallow cast-iron Dutch ovens and this fits the bill perfectly.
By all means, add some steamed or boiled potatoes alongside if you wish, but I'd prefer, by far, a baguette or two to be torn up and dunked into the flavorsome juices; though don't rule out the option of sourdough toast, which is the perfect vehicle for spreading the sweet-cooked garlic onto. Otherwise, some green beans or baby peas or a plain green salad is all you need for a sure-fire salivation-inducing supper.
Preheat the oven to 350 degrees F.
Heat the oil on the stovetop in a wide, shallow ovenproof and flameproof Dutch oven (that will ultimately fit all the chicken in one layer, and that has a lid), and sear the chicken over a high heat, skin-side down. This may take 2 batches, so transfer the browned pieces to a bowl as you go.
Once the chicken pieces are seared, transfer them all to the bowl. Finely slice the scallions, put them into the Dutch oven and quickly stir-fry them with the leaves torn from a few sprigs of thyme.
Put 20 of the unpeeled cloves of garlic (papery excess removed) into the pan, top with the chicken pieces skin-side up, then cover with the remaining 20 cloves of garlic. Add the vermouth (or white wine) to any oily, chickeny juices left in the bowl. Swish it around and pour this into the pan too. Sprinkle with the salt, grind over the pepper, and add a few more sprigs of thyme. Put on the lid and cook in the oven for 1 1/2 hours.
Make Ahead Note: Chicken can be browned and casserole assembled 1 day ahead. Cover tightly and store in the refrigerator. Season with salt and pepper and warm the pan gently on the stovetop for 5 minutes before baking as directed in recipe.
Making Leftovers Right: If I do have any chicken left over - and I don't think I've ever had more than 1 thigh portion - I take out the bone then and there and put the chicken in the refrigerator. Later (within a day or two), I make a garlicky soup, by removing the chicken, adding some chicken broth or water to the cold, jelled juices, placing it over a high heat and, when that's hot, shredding the chicken into it and heating it through thoroughly, till everything is piping hot. You can obviously add rice or pasta. Otherwise, mash any leftover garlic into the concentrated liquid (which will be solid when cold), chop up some leftover chicken, and put it all into a saucepan with some cream. Reheat gently until everything is piping hot, and use as a pasta sauce or serve with rice.