Dissolve yeast in warm water. Add next 6 ingredients plus 1 cup all-purpose flour. Beat on medium speed until smooth. Stir in enough remaining flour to form a soft dough (dough will be sticky)., Turn onto a lightly floured surface; knead until smooth and elastic, 6-8 minutes. Roll into an 18x12-in. rectangle. For filling, spread dough with butter, then combine sugar and cinnamon; sprinkle over dough to within 1/2 in. of edges., Roll up jelly-roll style, starting with a long side; pinch seam to seal. Cut crosswise in half to form 2 logs. Place logs side by side; pinch top ends together to seal. Using a sharp knife, cut logs lengthwise in half; loosely twist strips around each other. Pinch bottom ends together to seal. Shape into a coil; place on parchment. Transfer to a parchment lined 6-qt. slow cooker. Cover slow cooker with a double layer of white paper towels; place lid securely over towels. Let rise until doubled, about 1 hour., Cook, covered, on low until bread is lightly browned, 3-1/2 to 4 hours. To avoid scorching, rotate slow cooker insert a half turn midway through cooking, lifting carefully with oven mitts. Remove from slow cooker and cool slightly. Beat icing ingredients until smooth. Spread over warm roll.