Place a large bowl over a pot filled with water. Make sure the water doesn't touch the bottom of the bowl. Pour the chocolate chips into the bowl and bring the water to a simmer. You don't want a boil. This will slowly melt the chocolate chips.
While the chocolate chips are melting, in the microwave heat the peanut butter until it's more spreadable. You're going to need to be able to easily spoon the peanut butter.
When the chocolate is melted, remove it from the heat. Line a baking sheet with parchment and pour the chocolate over top. Spread it into a thin layer.
Drizzle your peanut butter on top and using a fork or toothpick swirl it into the chocolate mixture.
Sprinkle with sea salt and refrigerate for at least 1 hour.
When you're ready to serve, remove the parchment from bark and break it into free form pieces.
This bark is best stored in the fridge, but as long as it's in a cool dry place you can store it in a container and separate each layer with parchment or wax paper to prevent sticking. Bark is perfectly yummy up to 2 weeks.