Makes 2 loaves
Crumble yeast into small bowl. Stir in lukewarm water and sugar. Let stand until foamy, about 10 minutes.
Meanwhile, add molasses and butter to milk and stir until butter melts. Combine 2 cups all-purpose flour, bran, seeds and salt in large bowl. Whisk in yeast and milk mixtures until smooth, about 3 minutes. Using wooden spoon, mix in all-purpose flour 1/2 cup at a time until dough forms soft mass. Knead on heavily floured surface until smooth and satiny, kneading in more flour if sticky.
Grease large bowl. Add dough, turning to coat entire surface. Cover bowl with plastic. Let rise in warm draft-free area until doubled, about 1 1/2 hours.
Grease two 9x5-inch loaf pans. Gently knead dough on lightly floured surface until deflated. Cut in half. Pat each piece out into rectangle. Roll up jelly roll fashion, pinching seams to seal. Place seam side down in prepared pans. Cover with towel and let rise in warm draft-free area until doubled in volume, about 45 minutes.
Position rack in center of oven and preheat to 375 F. Bake until loaves pull away from sides of pans, about 45 minutes. Immediately remove from pans. Cool completely on racks.