In a large bowl, combine the popcorn, Golden Grahams, mini marshmallows, and chocolate chunks. Gently toss everything together so it’s evenly mixed without crushing the popcorn.
Drizzle the melted chocolate over the top, then toss again lightly until everything gets a thin chocolate coating.
Spread the mixture out on a parchment-lined baking sheet and let it sit until the chocolate sets.