1. Stir the water, skim milk powder, yeast and honey together and let sit 5 minutes. Stir in flours and salt. If using a stand mixer, knead with a dough hook for 8 minute on medium-low speed, and if kneading by hand, knead for 12 minutes. Place dough in a lightly oiled bowl, cover bowl with plastic wrap and place in a warm, draft-free place to rise for an hour.
  2. Punch down the dough and turn it out onto a lightly floured work surface. Divide dough into 2 pieces and roll out each piece into a rectangle 9-inches (23 cm) by 12-inches (30 cm). Roll up each piece of dough from the short end and place into a greased 9-x-5-inch (2 L) loaf pan with the seam facing down. Cover dough with tea towels and let rise 30 minutes.
  3. Preheat the oven to 375 ºF (190 ºC). Brush tops of loaves with the egg wash, sprinkle with the seeds (if using) and slice a lengthwise slit across the tops. Bake for 45 minutes. Immediately turn the loaves out onto a rack to cool completely before slicing.