Put popped corn in a large, lightly buttered bowl.
Melt Butter in medium saucepan. Stir in sugar, syrup and salt. Bring to a boil, stirring constantly. Boil 5
minutes. Remove from heat. Stir in soda and vanilla. Pour gradually over popcorn, mixing well. Turn into a large roast pan, bake 1 hour. Stir every 15 minutes. Remove from
the oven and cool completely. Break apart if necessary. Store in tightly covered container.