Spread Chex on a greased baking sheet. Preheat oven to 250 degrees.
Bring the butter, brown sugar and light corn syrup to a boil in a medium sauce pan. Once boiling, stir constantly for 1 minute. Remove from heat and add baking soda. Mix well.
Pour mixture over chex & mix until well coated. Place in the oven for 45 minutes, taking out to stir every 15 minutes. Let cool.
Once coating on Chex has cooled & set, place in large bowl & mix in the candy corn, caramel M&Ms and peanuts.