• Preheat the oven to 325°F.

For the crust:

• In the bowl of a food processor, process the crackers and sugar until finely ground. Add the butter and pulse until moistened. Use the bottom of a measuring cup, glass, or ramekin to press the crust mixture into the bottom and up the sides of a 9-inch pie plate. Bake until fragrant and golden brown, about 12 minutes. Cool completely on a wire rack.

For the pudding:

• Meanwhile, make the pudding. Put the gelatin in a small bowl, add the boiling water, and stir until dissolved. Set aside.
• In a medium saucepan, mix the sugar, cocoa, cornstarch, and salt. Gradually add the milk, whisking until smooth. Set over medium heat and cook, whisking constantly, until the mixture thickens and comes to a boil, about 10 minutes.
• Remove from the heat. Add the chocolate and stir until melted. Stir in the vanilla and reserved gelatin. Pour the mixture into the cooled crust.

For the topping:

• Cut the marshmallows in half lengthwise with a pair of scissors. Top the pie with the marshmallows, covering the entire surface. Use a kitchen torch to brown the marshmallows to your desired toastiness. Alternatively, place the pie pan on a baking sheet and broil for 2 minutes, watching the entire time to make sure it doesn’t scorch. Chill the pie in the fridge for at least 3 hours, or preferably overnight, until well chilled. Slice and serve!