Set out a large roasting pan and add in the corn cereal, rice cereal, pretzels, oat cereal, and mixed nuts. Toss well to combine.
In a small bowl, whisk together the butter, Worcestershire sauce, maple syrup, garlic powder, paprika, and salt. Pour the butter mixture over the cereal mixture and toss very well to combine and evenly coat.
Bake the nuts and bolts for 1 ½ to 2 hours or until the butter has been absorbed and the mixture is golden brown, stirring every 30 minutes or so.
Allow the nuts and bolts to cool completely then mix in the candy-coated chocolate, if using. Store in airtight containers for up to 1 month.