In a small bowl, combine bran and boiling water; set aside. In another bowl, dissolve yeast in warm water.
In a large bowl, cream shortening, sugar and salt. Add eggs and yeast mixture; mix well. Add bran mixture and 2 cups flour; beat well. Gradually add enough remaining flour to form a soft dough.
Turn onto a lightly floured surface; knead until smooth and elastic, about 6-8 minutes. Place in a greased bowl, turning once to grease top. Cover and let rise until doubled, about 1 hour.
Punch dough down. Turn onto a lightly floured surface. Divide into six portions; divide each into 12 pieces. Shape each into a ball; place three balls in each greased muffin cup. Cover and let rise until doubled, about 1 hour.
Bake at 350° for 15-18 minutes or until lightly browned. Remove from pans to wire racks.