Add Chex, pretzels, crackers, and nuts to the crock of a slow cooker, stirring well.
9 cups Chex cereal, 2 cups tiny pretzels, 1 ½ cups cheese snack crackers, 1 ½ cups mixed nuts
In a small bowl, whisk together butter, Worcestershire sauce, seasoning salt, garlic powder, and onion powder until well combined and dissolved.
½ cup butter, ¼ cup Worcestershire sauce, 3 teaspoons seasoning salt, 1 teaspoon garlic powder, ½ teaspoon onion powder
Drizzle the butter sauce evenly over the top of the mixture. Toss well to combine.
Cover and slow cook on low for 3 hours, stirring every 45 minutes so that the mixture does not burn.
Spread the mixture out onto two parchment-lined baking sheets to cool to room temperature.
Store leftover mix in a sealed container for up to 3 weeks.