For the crust: Preheat the oven to 375 degrees F. Put the graham crackers in the food processor and pulse until small crumbs form. Mix the sugar and melted butter into the cracker crumbs. Press about 2 teaspoons of the mixture into each well of a nonstick mini muffin pan, about 20 wells. Bake the pie shells for about 6 minutes. Let the shells cool and set aside.
For the marshmallow topping: Place the 1/4 cup water in a standing mixer bowl and sprinkle the gelatin on top. Let the mixture sit for 15 minutes.
For the chocolate filling: Meanwhile, while the gelatin is sitting combine the entire milk chocolate candy bar and the half-and-half in a microwave-safe bowl. Microwave for 45 seconds; stir until smooth. Place about 1 teaspoon chocolate filling into each of the cooled shells.
In a medium saucepan over medium heat, mix the sugar, corn syrup, 1/8 teaspoon salt, and cold water together, then heat until the sugar is dissolved and mixture comes to a boil. Continue heating the mixture until the temperature reaches approximately 240 degrees F on a candy thermometer. Remove from the heat.
Take the sugar syrup mixture off the stovetop and slowly combine with the gelatin mixture in the standing mixer bowl. Add the vanilla.
On high speed, mix the syrup and gelatin mixture for approximately 10 minutes, until thick and fluffy; it should resemble marshmallow. Spoon the marshmallow over the chocolate filling.
Using a small torch, toast the top of the marshmallow pies for a 'just roasted over the campfire' look. An alternative would be to use the oven broiler, taking out the mini pies just after the tops turn golden brown.
Grate a few frozen chocolate pieces using a rasp, zester, or vegetable peeler over the mini pies for garnish. Enjoy!
Cook's Note: The toasty top of the marshmallow, created with a mini torch, enhances the flavor of the pie and perfectly mimics that of a real s'more. Also, the unique miniature size (using a mini muffin tin) provides you with just the right serving size; perfect for kids to handle as well!