Preheat oven to 250 degrees F. Place popcorn in well-greased pan. In large heavy saucepan, melt butter; stir in sugar, syrup and salt. Bring to a boil. Boil for 5 minutes over medium heat without stirring. Remove from heat and stir in vanilla and soda. Pour syrup over popcorn and stir well. Bake for 1 hour, stirring every 15 minutes. When cool separate kernels, store tightly covered. |