6 to 7 qt. fresh popped popcorn
1 c. butter
2 c. brown sugar
1/2 c. light Karo
1 tsp. salt
1 tsp. vanilla
1/2 tsp. baking soda

Preheat oven to 250 degrees. Stir together the butter, brown sugar and Karo in a heavy skillet over medium heat. Boil for 5 minutes, remove from heat. Add baking soda and vanilla. Drizzle this syrup over the popcorn, which has been placed in a large buttered baking pan, stir. Bake for 1 hour, stirring every 15 minutes. When cool, store in airtight container.