Line a large baking sheet with parchment paper. Spray it lightly with non-stick spray or rub it with a bit of butter. This is crucial for rolling later.

In a large heavy-bottomed pot, melt your butter over low heat. Once melted, add the mini marshmallows. Stir constantly until they are smooth and glossy. Remove from heat immediately so the marshmallows don't get tough.

Fold in your vanilla extract and a pinch of salt. Gently stir in the Rice Krispies cereal and about half of your crushed graham crackers. You want every piece of cereal to be coated in that sticky goodness.

Transfer the mixture to your prepared baking sheet. Using a buttered spatula or another piece of parchment paper on top, press the mixture into a flat, even rectangle. You want it to be about half an inch thick.

Spread the marshmallow fluff over the surface, leaving a small border at the edges. Next, drizzle your melted Hershey's chocolate bars over the fluff. Sprinkle the remaining graham cracker crumbs over the chocolate.

Starting from one of the long ends, carefully use the parchment paper to lift and roll the treats into a tight log. Work slowly to keep the s'mores rice krispy swirls intact.

Wrap the log tightly in the parchment paper and let it set in the fridge for at least 30 to 45 minutes. This makes slicing much easier. Once firm, use a sharp serrated knife to cut 1 inch thick s'mores rice krispie treat roll slices.