Add the Chex, pretzels, Cheerios, and peanuts together in a large microwave-safe mixing bowl, and gently stir a bit to combine.In a separate bowl, whisk together the melted butter, worcestershire sauce, seasoned salt and garlic powder together until combined. Drizzle half of the sauce evenly over the Chex mix. Then give the mix a gentle stir to combine. (I like to stir with a rubber spatula, to help prevent breaking the Chex.) Repeat by drizzling the remaining sauce over the Chex mix, and stir again until combined.Microwave uncovered on high 5 to 6 minutes, thoroughly stirring every 2 minutes.Spread the mix out on parchment paper or paper towels until it has cooled to room temperature. Store in airtight container for up to 3 weeks.