Stir together flour, yeast, salt, and wheat gluten in large bowl.
Add water and mix well with a spoon.
Optional: Stir in variation ingredients (see below).
Cover with plastic wrap and let sit in a place that stays at least 70 degrees.
After 18 hours (or 12 to 24, close to 18 is best), move the dough to a floured board. Use enough flour so it doesn't stick.
Fold once or twice so it is not so spread out. Use flour so you can handle the dough, which will be wet and sticky. Whole wheat flour works best here even for white bread. Corn meal also works well.
Cover again with the plastic wrap and let the dough rest for 15 minutes.
Use an oil spray to grease a bread pan. Any old bread pan will do (glass or metal) but be sure to oil it. (Here we differ from the New York Times recipe which calls for a heavy iron covered pot in which to bake the bread in order to get a better crust. We have found the extra trouble is not worth the difference but you may think differently.)
After the dough has rested 15 minutes, move it to the bread pan. The dough will be sticky; use a spatula to get it out of the bowl.
Cover with a cloth and let rise for two hours. The white bread rises a lot but we have found that the whole wheat version does not rise quite as much and the resulting bread is a little heavier but still very good.
After the bread has risen for two hours, cover with foil and bake for 45 minutes in an oven preheated to 450 degrees, removing the foil after 30 minutes.