3 Qts of popcorn, kept warm in 250 degree oven

Mix together on medium heat, stir frequently. Bring to a boil and boil with out stirring for 4 minutes
1 cup brown sugar, packed
1/2 cup (1 stick) margarine
1/2 cup Karo
1/2 tsp salt

Take off heat, add:
1/2 tsp soda
1/2 tsp vanilla

Stir in well and add to popcorn. Bake 1 hour; stir every 15 minutes.