12 large hard-shell clams, 4 to 5 1½ c soft fresh crumbs made from inches in diameter, shucked, home-made type white bread, with the deeper half of each pulverized in a blender or shell reserved finely shredded with a fork 2 T butter, softened, plus 4 T 3 T finely chopped fresh parsley butter, plus 2 T butter, chilled ¼ tsp crumbled dried thyme and cut into ¼-inch bits ½ tsp salt ½ c finely chopped onions Freshly ground black pepper 1 tsp finely chopped garlic ------------------------------Preheat the oven to 400°. Wash the clams in a sieve under cold running water, spread them on paper towels and pat them dry. Then put the clams through the coarsest blade of a food grinder into a small bowl. Scrub the shell halves under hot running water and dry them completely. With a pastry brush, spread the 2 tablespoons of softened butter evenly over the inside surfaces of the shells.
In a heavy 10- to 12-inch skillet, melt 4 tablespoons of butter over moderate heat. When the foam begins to subside, add the onions and garlic and, stirring frequently, cook for about 5 minutes until they are soft and translucent but not brown. Add the ground clams and stir for about 2 minutes. When the clams glisten with the butter, add the bread crumbs. Still stirring from time to time, continue to cook until the crumbs are golden brown. Remove the pan from the heat and stir in the parsley, thyme, salt and a few grindings of pepper. Taste for seasoning.
Mound the clam-and-crumb mixture in the buttered shells, dividing it evenly among them. Scatter the butter bits over the tops. Arrange the shells side by side on a large jelly-roll pan. Bake in the upper third of the oven for 10 to 12 minutes, or until the crumbs are a rich brown color. Serve at once. Serves 6 as a first course.