Prepare the Popcorn: Pop your popcorn using an air popper or on the stovetop. Make sure to remove any unpopped kernels. Place the popcorn in a large mixing bowl.
Mix the Dry Ingredients: In a separate bowl, combine the pretzels, salted peanuts, M&Ms, and dried cranberries. Set aside.
Make the Sweet Coating: In a small saucepan, melt the butter over medium heat. Whisk in the brown sugar, vanilla extract, salt, and a dash of cinnamon if you like. Cook and stir until the sugar is completely dissolved.
Combine Everything: Pour the sweet coating over the popcorn and gently stir to coat. Next, add the pretzels, peanuts, M&Ms, and cranberries to the popcorn mixture. Stir well until everything is evenly coated.
Bake for Crispiness (Optional): Preheat your oven to 250°F. Spread the popcorn mix onto a large baking sheet and bake for about 30 minutes, stirring halfway through. This step ensures that the mix stays crunchy and crispy.
Cool and Serve: Remove the popcorn mix from the oven and let it cool completely. Break it into clusters if needed and serve immediately or store in an airtight container.