Line an 8" x 8" baking pan with foil, leaving an overhang, and spray with non-stick cooking spray. Set aside.
Chop candy corn and pretzels into desired sizes. Set aside.
In a medium saucepan over low heat, melt the white chocolate. If using white chocolate chips, add 1 teaspoon of shortening to keep everything smooth. Pour into prepared pan and spread evenly with a spatula or knife.
Sprinkle chopped candy corn and pretzels onto white chocolate. Using a piece of wax or parchment paper, press down on candy corn and pretzels. Allow to cool in refrigerator for 10 minutes.
Lift bark using foil overhangs out of pan and, using a sharp knife, cut into desired size pieces. Bark can be kept in an airtight container at room temperature up to 5 days.