For the sponge:
- 2 cups lukewarm water (100°F)
- 1 Tbs. active dry yeast
- 1 1/2 cups medium-grind rye flour
- 1/4 cup unsulfured light molasses
- 3 Tbs. firmly packed dark brown sugar
- 1 1/2 tsp. fennel seeds, crushed
- 1 1/2 Tbs. canola oil, plus more for greasing
- 2 tsp. salt
- 3 1/2 to 4 cups bread flour, plus more as needed
- Rye flour or brown rice flour for dusting
Add the oil, salt and 1 cup of the bread flour to the sponge and switch to the paddle attachment. Beat on medium speed for 1 minute. Beat in the remaining bread flour, 1/2 cup at a time, until the dough pulls away from the bowl. Switch to the dough hook. Knead on low speed, adding bread flour 1 Tbs. at a time if the dough sticks, until smooth and elastic but slightly tacky, about 5 minutes. Transfer to an oiled deep bowl and turn to coat. Cover loosely with plastic wrap and let rise at room temperature until doubled in volume, 1 1/2 to 2 hours.
Lightly grease two 8 1/2-by-4 1/2-inch loaf pans. Turn the dough out onto a lightly floured board and divide into 2 equal portions. Knead lightly a few times, then pat each portion into a long rectangle. Fold each rectangle like a letter, overlapping the short sides in the middle, and press to flatten. Beginning at a narrow end, tightly roll up the dough into a thick log, then roll back and forth with your palms until it is the same length as the pan. Pinch the ends and the long seam to seal, dust lightly all over with a little rye flour and place in the pans, tucking the ends under to make a neat, snug fit. Cover loosely with plastic wrap and let rise at room temperature until the dough is about 1 inch above each pan rim, about 1 hour.
Preheat an oven to 350°F.
Using a thin, sharp knife, gently make 3 shallow diagonal slashes across the top of each loaf. Bake until the loaves are golden brown and crusty, 50 to 55 minutes. Turn the loaves out onto wire racks and let cool completely. Makes two 8 1/2-by-4 1/2-inch loaves
Adapted from Williams-Sonoma Collection Series, Bread, by Beth Hensperger (Simon & Schuster, 2002).