How to Make It
Remove the container from the bread machine. Pour 1/2 cup of the milk into a small saucepan and add the butter. Swirl the pan over moderate heat only until the butter has almost melted. Remove from the heat and cool the liquid by pouring in the remaining 1 cup of milk. If you are using the starter, stir 1/2 cup of it into the liquid; it will not break up completely. Pour the liquid (with or without the starter) into the container and, without stirring, add the salt, sugar and flour. Then make an indentation the size of a soupspoon in the flour and add the yeast. Replace the container securely and set the machine at least 1 foot from the edge of the counter. (Machines can walk when then kneading is vigorous—Julia Child's did.) Program for "dough" and start the machine. After 10 minutes of kneading, check the dough. If it feels wet and sticky, keep the machine running and sprinkle in a tablespoon or two of flour; if dry, add drops of water. When the cycle ends, after about 1 hour and 45 minutes, the risen dough will have been deflated by the machine.
Remove the dough from the container and give it a vigorous 1 minute of kneading on a lightly floured work surface. You should have a smooth, supple dough. Return the dough to the machine for its second rise. In 1 to 1 1/2 hours, it should have risen to the top of the container again; a slight overrise will not hurt it.
Transfer the risen dough to your lightly floured work surface. With lightly floured hands, firmly press and pat the dough into a 10-inch rectangle with the ends to your left and right. With the side of your hand, firmly press a lengthwise trench along the center of the dough and fold it in half, bringing the top long edge down to meet the bottom. Press firmly to seal the edges. Rotate the dough, seal side up and repeat the process. Transfer the dough, seal side down, to the prepared pan.
Drape a lightly floured towel over the pan. Let the dough rise at 72° to 75° until the pan is four-fifths filled; this should take no more than an hour. Meanwhile, preheat your oven to 425° and set a rack in the lower third of it.
Lay the aluminum foil, buttered side down, over the pan and place the baking sheet on top. Set the pan in the oven and center the weight on the baking sheet. Bake for about 35 minutes, checking several times to be sure the rising dough has not dislodged the weight.
To test, rapidly remove the pan and close the oven door. Turn the loaf out onto your work surface. It should easily come out of the pan and be lightly browned all over. It's very important to note that the thump method is not a dependable test. Poke an instant-read thermometer into the center of the loaf through the underside and let the mercury climb. If it reaches just over 200° to about 210°, the bread is done. If not, return the bread to the pan and bake another 10 minutes or so.
Set the loaf on a rack on its side and let cool thoroughly, about 2 hours. Bag it in plastic. Its flavor and texture will improve after 24 hours, and if you plan to slice it very thin, give it a 2-day wait. Freeze for longer storage.
You can, of course, make this bread entirely by hand, or you can use a heavy-duty mixer to mix and knead the dough. If you are doing it by hand, let the dough double in bulk at both the first and second risings.
For a traditional humped loaf of white bread, let the dough fill the pan completely during the final rise. Bake the bread uncovered in the preheated 425° oven for about 20 minutes, or until puffed and brown. Cover the loaf loosely with foil, reduce the heat to 375° and bake for 20 to 30 minutes longer.
This recipe also makes delicious raisin bread, and Julia Child particularly likes it baked in a closed pan. Follow the same procedure, but knead 1 1/2 cups of currants into the dough by hand, following the first rise. The second rise will go a little faster because of the sugar content of the currants.