Preheat oven to 225 degrees. Line 2 large baking sheets with parchment paper and spritz with non-stick cooking spray. Divide popcorn between the two baking sheets.

In a medium to large saucepan, melt the butter over medium heat, stirring to avoid browning. To the pot, add the brown sugar, syrup, and salt.

Bring the syrup to a boil and then reduce the temperature allowing the syrup to boil for about 3 minutes or until a candy thermometer reaches soft-ball stage (238 degrees.)

Whisk in the vanilla and baking soda, expecting the chemical reaction to cause the syrup to bubble up.

Pour caramel over the popcorn, tossing to coat thoroughly.

Bake for 40 minutes, tossing halfway.

Remove the popcorn from the oven and lift popcorn from baking sheets using the parchment paper and allow to cool completely.

Once cooled, drizzle with melted chocolate and sprinkle with Rolo candies.

Allow the chocolate to set completely before packaging or serving.