Preheat the oven to 250 degrees. Place the butter, cut into 3 pieces, in a large roasting pan or foil pan and put it in the oven to melt, you don't have to wait for the oven to preheat for this step. Keep an eye on it and take it out as soon as all the butter is melted.

Meanwhile, in a small bowl, combine the seasoned salt, garlic powder and onion powder and stir together. After the butter has melted, add the seasoning mix to the butter and swirl around to incorporate, next add the worcestershire sauce and continue to swirl the pan until everything is combined. Add the rest of the ingredients to the roaster and gently stir to combine until the sauce is evenly distributed over the cereal mixture.

Cook in the preheated oven for 1 hour, stirring gently every 15 minutes. Spread the cooked Chex Mix out onto paper towels on the counter to cool before storing in an airtight container.