My Grandma Workman used to send this to us every Christmas, and I remember one year she wasn't able to and my Dad felt like it wasn't even Christmas. In the early days of Southern Utah, that was just about their only treat...corn bread and molasses. This candy tastes like molasses in hard candy form and that's basically what it is. However, I prefer not to wrap it in foil like my Grandma did. It always stuck and we used to have to tear it off in pieces. Try waxed paper?! It is really good, and brings back such memories.
Stir the brown sugar, molasses, butter and vinegar together. Boil them to the hard ball stage (drop forms a hard ball in ice cold water). Add the baking soda and stir rapidly. Turn the mixture at once into a buttered shallow pan 8" square. If desired, spread chopped nuts over the top. Cool the candy and break it into pieces for serving.