In a large mixing bowl, combine cereals, pretzels, Cheez-its, peanuts. You could mix it directly in the dutch oven you are going to bake it in but I find it easier, and less spillage, to do it in a large mixing bowl and then put it into the dutch oven.
In a medium size bowl, melt butter and add in Worcestershire sauce and seasonings. Stir to combine.
Mix the cereal/ cracker mixture.
Pour butter mixture over the top and stir to coat cereal mixture.
Add mixture to dutch oven or roasting pan.
Bake for 1 hour, stirring every 15 minutes.
Pour mixture out onto parchment paper and allow to cool.
Store in an airtight container at room temperature for up to two weeks.
Notes
Microwave Version: Microwave the Chex mix on HIGH for 6 minutes, stirring every 2 minutes. Depending on the size of your microwave you may need to do this in batches. Make sure you are using a microwave safe bowl.Variations:
If you don't like wheat chex, leave them out and use more corn and or rice chex. You can customize the mix to your personal preference.
Switch up the nuts. Instead of peanuts, use cashews or a mixture of nuts. The original chex party mix recipe called for mixed nuts.
Instead of Cheez Its you can use a bagel chips, goldfish crackers or broken up melba toast.