Line a small baking tray with parchment paper and set aside.
Add the chocolate chips to a microwave safe bowl and microwave in 30-second intervals until smooth.
Pour the melted chocolate (except about 2-3 tablespoons) onto the prepared baking sheet and smooth out towards the edges, but don't spread it too thin or the bark will be flimsy.
Immediately add the miniature marshmallows and graham cracker pieces and lightly press them into the melted chocolate.
Take the remaining 2-3 tablespoons of melted chocolate and drizzle it over the top of the marshmallows and graham crackers.
Place the tray in the refrigerator to chill for 10 minutes.
Remove the tray from the refrigerator and break the hardened chocolate pieces into large chunks.
Serve chilled or at room temperature.