Ina writes: Well, to continue and go on, after a late dinner I made donuts, for I must have fresh donuts for Christmas, and you know “do-nuts and coffee never hurt anyone.” That evening after all was cleared away, Dad popped two kettlefuls of lovely corn and we sugared one and put taffy over the other. We heaped a large platter with balls till Dad said, “Oh, that’s enough,” for he wanted some left to eat. Well, I sent him off to the living room to eat and read. Then I prepared my dressing and sweet potatoes for the morrow and put my buns to rise, for I’d baked lite bread and roasted beef too. At last I repaired to my seat before the fire with a pan of sugared corn, nuts and candy and filled eleven little Xmas boxes for the tree. Then I fell upon the boxes. Ethel’s was wrapped with green string and I cut this off to tie on packages, being foolish about green string for my tree packages . . . The packages were all so pretty and I had a great time -- hung them on the tree and under it. Ina Dobson, Christmas 1933
I didn't find a recipe for any kind of popcorn coating in Ina's recipe box, so I don't know how she did it. My dad, Vance, thought that a molasses-based popcorn was the finest kind of treat. He loved to cook, but he always sought to "improve" any recipe with which he worked. To his way of thinking, a recipe was meant to be changed.
Here's one of Vance's recipes for a double batch of caramel corn:
1 cup white corn syrup
1/3 cup molasses
1/2 cup butter or margarine
1 1/2 tsp soda
Combine all ingredients except soda. Boil to 250 degrees. Dissolve soda in one tbsp hot water and add to syrup. Pour over two large containers [roasting pans] of corn (about 5 quarts each). Spread on cookie sheets and bake at 200 degrees until crisp.
If you want a simpler recipe for a smaller batch, you might try Betty Crocker (here). I would.