Line a large baking sheet with parchment paper and set aside.
Unwrap chocolates and place in a large microwave safe bowl.
Microwave at 50% power in 30 second intervals until chocolate is melted and creamy.
Pour chocolate on parchment lined baking sheet and spread evenly making a 8×12 inch rectangle.
Heat marshmallow fluff in the microwave at 50% power in 10 second intervals until easy to stir. Dollop fluff on top of chocolate. Using the back of butter knife, gently swirl marshmallow fluff in chocolate.
Sprinkle top with graham cracker pieces.
Place in the refrigerator for a few hours until harden. Break into pieces and store in an airtight container in the refrigerator until ready to serve.