Preheat oven to 350ºF. Line a baking sheet with parchment paper or silicone baking mats. Set aside.
Make the ice cream base: In a small pot, simmer cream, milk, sugar and salt until sugar completely dissolves, about 5 minutes. Remove pot from heat.2 cups heavy cream
In a separate bowl, whisk egg yolks.6 large egg yolks
Whisking constantly, slowly whisk about a third of the hot cream into the yolks, then whisk the yolk mixture back into the pot with the cream.
Return pot to medium-low heat and gently cook until mixture is thick enough to coat the back of a spoon (about 170ºF on an instant-read thermometer).
Strain through a fine-mesh sieve into a bowl and set aside to cool for a few minutes.
Toast the marshmallows: Spread the marshmallows out on prepared baking sheet. Place marshmallows in oven for 5 minutes. 10 ounces marshmallows
Note: for the next step, you can either use the broiler or a kitchen torch to toast the marshmallow. Boiler: place the oven rack as high as possible and watch the marshmallows very closely to ensure they don't burn. This should take about 2-3 minutes at most.Kitchen torch: toast the tops and sides of the marshmallows, then rotate so that they are evenly toasted on each side. In a blender, add the ice cream base and the toasted marshmallows and puree until smooth.
Pour mixture into a clean bowl, cover and chill completely in the fridge, at least 4 hours or overnight, until completely cool.
Once ice cream base is completely cool, churn in an ice cream maker according to manufacturer’s instructions.
While the ice cream is churning, chop the chocolate bars in bite-sized pieces and crush the graham crackers into small pieces. You can do this by placing the graham crackers in a sealed zip-top bag then rolling over them with a rolling pin or you can pulse in a food processor a couple of times. You want pieces of graham cracker, not crumbs. 4 Hershey's Bars
Once ice cream has finished churning, pour half into an 8x8-inch baking pan lined with parchment paper or wax paper.
Sprinkle half the graham cracker crumbs and half the chocolate over top. Repeat with remaining ice cream, graham crackers, and chocolate. Serve directly from the machine for soft serve, or store in freezer until hardened.