You can buy chernushka "black caraway" in some health food stores or from mail-order. They are nothing like the familiar caraway seeds. This bread is a New York specialty, usually made in bakeries.

1. Combine 1/2 cup of the warm water, the yeast and sugar and let stand until doubled in bulk, about 10 minutes. 2. Dissolve the salt in the remaining warm water in a mixing bowl. Mix in the sourdough starter, then the yeast mixture, then the gluten flour and 2 cups of the all-purpose flour; make a soft dough. 3. Spread 1 1/2 cups flour on the kneading surface and turn the dough out onto it. Knead, adding more flour if necessary to make a soft dough that will hold its shape. Do not overknead.. the dough should be only slightly elastic, even a bit sticky. 4. Form the dough into a ball and put in an ungreased bowl; cover with plastic, and let rise until doubled in bulk, about 1 1/2 hours. 5. Turn the dough out onto a lightly flour surface and knead it a few strokes to expel air. Cover with a towel and let rest for 15 minutes. 6. Divide the dough in half. Form each half into a loaf by flattening in to an inch-thick oval about 12 inches long, then rolling it up from one long side. Pinch the seam closed. Shape the ends of the oval loaves neatly and plce them on two cornmeal-dusted baking sheets, seam down. Cover with towels and let rise until "three-quarters proofed, " or not fully doubled.