Preheat your oven to 275°F (135°C). Prepare two baking sheets by lining them with parchment paper. This makes cleanup a breeze!
In a super large bowl, gently combine the corn Chex, rice Chex, pretzels, broken bagel chips, cheese crackers, and peanuts. Give it a good mix so everything is evenly distributed.
Grab a small saucepan and melt the butter over medium heat. Once it's liquid, stir in the corn syrup, Worcestershire sauce, all the delightful spices (ancho chile powder, hot smoked paprika, garlic powder, chipotle powder), brown sugar, Kosher salt, and black pepper.
Bring this savory mixture to a gentle simmer and let it cook for about 2-3 minutes, allowing the flavors to meld beautifully.
Immediately pour the warm spice mixture over the snack mix in the large bowl. Stir diligently until every single piece is coated with the delicious seasoning. You don't want any plain bits!
Divide the coated snack mix evenly between your two prepared baking sheets, spreading it out into a single, even layer.
Bake for 1 hour and 20 minutes. Remember to stir the mix every 20 minutes, and rotate the baking sheets from top to bottom and front to back each time you stir. This ensures even baking and perfect crispiness.
Once baked, transfer the trays to wire racks and let the BBQ Chex Mix cool completely. It will get even crispier as it cools!
Store your finished snack mix in a gallon-size zip-top bag or an airtight container. It stays fresh and tasty for up to a week. Enjoy your homemade, flavorful snack!