Preheat oven to 250F. Line a large baking sheet with parchment paper.
In a large bowl, mix together the gluten-free corn Chex cereal, gluten-free rice Chex cereal, gluten-free pretzel twists, gluten-free cheese crackers, roasted peanuts, and roasted cashews. Set aside.
Melt the butter in the microwave or in a small pot on the stove-top over low heat.
Once melted, add the worcestershire sauce, Italian seasoning blend, garlic powder, onion powder, and salt until combined.
Pour the butter mixture over the chex mix and carefully stir until the cereal and crackers are completely covered.
Pour the mixture onto the prepared baking sheet and spread into an even layer.
Bake at 250F for 45 minutes, stirring every 15 minutes to make sure that the chex mix does not burn.
Remove from the oven and let cool completely before serving.