In a 5 quart pan, heat shortening, sugar and molasses on low, stirring constantly until sugar is dissolved. Remove from heat.
Add cinnamon, baking soda and salt. Stir in flour, 1 cup at a time, until dough can be formed into a ball.
Using remaining flour, lightly flour a wooden board. Turn dough onto the board; knead until even in color and smooth (not crumbly or dry), adding more flour if needed.
Form into a log. Cut into 5 equal pieces; wrap in plastic wrap.