A recipe for old fashioned popcorn balls?

My family lost a recipe on making popcorn balls. This was a long tradition to making it around the holidays. I remember it is made out of molasses and cream of tartar and other ingredients (heated to candy making temperature) and pour over popped popcorn, and use butter to press into balls. I believe this recipe was based in my dad's native Maine state. If I could make something similar, I think that would be a great gift for my dad for christmas and to show to his grandchildren (my niece, nephews and son)