Preheat the oven to 250 degrees F, and lightly grease a baking sheet.

Place the popcorn in a large mixing bowl, along with the nuts.

Melt the butter in a medium saucepan over low heat.

Stir in the brown sugar, corn syrup, and salt.

Increase the heat to medium and bring the mixture to a boil, stirring.

When the caramel comes to a boil, reduce the heat to medium low and allow to simmer, stirring, for 3 minutes (or until the temperature is registers about 235 degrees F on a candy thermometer).

Remove the pot from the heat and stir in the vanilla and baking soda (the mixture will foam up).

Slowly drizzle the mixture over the popcorn, while stirring/tossing the popcorn to coat it with the hot caramel. (It might be easier if you have a kitchen helper. One can pour while the other stirs.)

When the popcorn is well coated with caramel, spread it out in an even layer on a greased baking sheet.

Bake for 1 hour.

Allow to cool completely, then drizzle with melted white chocolate and melted dark chocolate.

Let the chocolate set, then break the moose munch into chunks and package up in mason jars, paper boxes, or cello bags for gifting.