6 quarts freshly popped popcorn
1 cup butter
2 cups brown sugar
3/4 cup light corn syrup
6 ounces semi-sweet chocolate
1 teaspoon salt
1 teaspoon vanilla extract

Heat oven to 200°F. Combine butter, brown sugar and corn syrup in saucepan. Bring to boil over medium-high heat and boil 5 minutes. Remove from heat and stir in chocolate, salt and vanilla. Let stand, stirring occasionally, till chocolate is melted. Place popcorn in large roasting pan and pour chocolate over, tossing gently to coat well. Bake 30 minutes, stirring occasionally. Pour in even layer onto waxed paper and let cool completely.