Preheat pellet grill or smoker to 250 degrees F. *I chose to use competition blend wood pellets from B&B.
In a small saucepan, melt the unsalted butter. Add the Worcestershire sauce and buffalo sauce to the melted butter. Stir to combine. Once combined, simmer for 1-2 minutes, then remove from the heat to cool slightly.
Combine granulated garlic, seasoned salt, all purpose seasoning, and cayenne pepper in a medium bowl. Mix well and set aside.
Mix together all cereal, dry snacks, and nuts. *I find it easiest to add all dry ingredients to a large, scent-free trash bag, but you can also use large mixing bowls.
Add roughly ⅓ cup of the melted butter mixture at a time to the dry cereal snack mixture (in the trash bag or mixing bowls). After adding each ⅓ cup of liquid, toss the cereal mixture to coat it with the butter liquid. Continue adding the wet ingredients and mixing with the snack mixture until done. When mixing, be careful not to crush the cereal pieces.
When all of the wet ingredients are mixed in, lightly sprinkle in the seasoning mixture, about a small handful at a time. Toss the cereal snack mix in between adding the seasoning mixture so that the cereal gets evenly seasoned, just like you did with the wet ingredients.
Divide the Chex Mix between 4 large baking sheets in a thin, even layer. If you don't have 4 large baking sheets, you can also use shallow baking dishes. *If you need to use a smaller number of deeper cooking pans, you will need to smoke the Chex Mix longer.
Taste the Chex Mix for seasoning, and add another light dusting of seasoned salt or all-purpose seasoning if needed before smoking the mix.
Place the baking sheets of Chex Mix on the grill. Smoke for about 1 hour and 15 minutes, mixing every 15-20 minutes so the mix cooks evenly. The smoked Chex Mix is done when it is fully dried out and nicely crispy.
When done, turn off the smoker and allow the smoked Chex Mix to cool inside the smoker with the lid closed.
When Chex Mix is fully cooled, serve immediately or transfer to gallon-sized Ziploc bags to store.