Cover a large baking sheet with parchment paper and set aside.
In a liquid medium microwave safe bowl, heat the coconut oil, peanut butter, maple syrup and 100% dark chocolate on high heat for 30 seconds. Stir and repeat until completely smooth. Add the dark chocolate cocoa powder and mix again until smooth. Set aside.
In a medium microwave safe bowl, melt the cocoa butter in the microwave. Whisk in the milk powder, pure maple syrup, vanilla extract, and sea salt until smooth. (You can use a blender to get it extra smooth if desired.) Put white chocolate in piping bag and cut a small tip off the corner and set aside.
Pour the reserved dark chocolate peanut butter mixture on the prepared baking sheet and spread into a an even 1/2 inch square layer. Once you have the swirls take a toothpick and start at the center of each swirl and gently pull outward until the en of the swirl. Repeat the process all the way around the swirl until you complete it and the swirl looks like a spiderweb! Once you repeat the process on all swirls your spiderweb bark is complete.
Place in the freezer for 10-20 minutes to set. Keep in an air tight container in the freezer for up to 3 months.