I did a demo on The Daily Dish (chn 30) last week. Here's the clip to making Chocolate Drizzle Popcorn
8 cups popped popcorn
½ cup packed brown sugar
4 Tbsp. butter
2 Tbsp. light corn syrup
¼ tsp. baking soda
1/3 cup white chocolate chips
Place popped popcorn in a large mixing bowl. In a medium sauce pan melt brown sugar, butter and corn syrup together over medium heat. Remove from heat and add baking soda. Pour over popcorn and stir until coated well. Spread out on a cookie sheet and allow to cool for 10-15 minutes.
Put chocolate chips in a microwave safe bowl and microwave at half power for one minute. Stir chips and cook again at half power for thirty seconds - stir. Continue cooking at half power for thirty second intervals until chips are melted through and runny. Drizzle white chocolate over cooled popcorn. Put cookie sheet in the fridge until chocolate sets. Can be stored at room temperature in an air-tight container.