Preheat oven to 300 degrees F. Line a baking sheet with parchment paper.
Combine the chex, pretzels, cheez-its, cashews, peanuts and pepitas in a large bowl.
Heat a small saucepan over medium-low heat and add butter. Whisk constantly until the butter is sizzling and brown bits appear on the bottom of the pan, about 5 to 6 minutes. Constantly stir! Remove the butter from the heat immediately and pour it into a bowl. Whisk in the brown sugar, garlic powder, smoked paprika, salt and pepper until combined. Pour the seasoned butter over the chex mixture and toss well for at least 5 minutes until everything is moistened and covered. Spread the mixture out on the baking sheet. Bake for 1 hour, tossing every 15 minutes. Remove from the oven and let cool slightly.
To make the bacon fat popcorn, heat a large nonstick skillet or pot over medium heat. Add the bacon grease and once it’s melted, add in the corn kernels. Shake the pan slightly and as soon as the kernels start popping, cover and continue to shake the pan until it’s all popped. Remove from the heat. As soon as the chex mix comes out of the oven, I like to stir the popcorn into the mix in batches so it can get slightly seasoned too. You can also drizzle it with bacon fat or butter and salt and pepper.
Toss the chex mixture, popcorn and wasabi peas together to create your mix. Serve! This can be stored in a resealable plastic bag (once cooled) for a week or so. I find that after that it does start to get a little stale or soggy.