Preheat oven to 350 degrees F.

In a large bowl, toss together the graham cracker crumbs, melted butter, sugar, and salt until well combined. Pour out onto a greased 17x12-inch (half size) baking pan. Using your hands or the bottom of a measuring cup, press out the crumbs onto the bottom of the pan until evenly flat. Bake until lightly golden brown around the edges, about 10 to 12 minutes. Remove from the oven, set aside, and let cool completely.

To make the filling, in a large saucepan, whisk together the sugar, cocoa powder, cornstarch, salt, and milk. Set over medium-high heat and cook until the mixture thickens and begins to bubble, stirring constantly, about 5 minutes. Remove from heat and whisk in the butter and vanilla extract. Pour out onto the cooled crust, through a fine mesh strainer. Then using a spatula, spread the pudding into an even layer. Cover the top directly with plastic wrap and chill in the fridge for at least 3 hours, or until firm. You could also pop it in the freezer for about 1 hour. It should be completely chilled and set.

To make the topping, place the egg whites and sugar in a heat-proof bowl. Set it over a pot of simmering water, making sure the bottom of the bowl doesn't touch the water. Cook, stirring often, until the sugar has dissolved, about 3 to 5 minutes. Transfer to a bowl of a stand mixer and pour in the vanilla and cream of tarter. Beat on medium speed with the whisk attachment until firm. Increase the speed to high and beat until stiff and glossy, 8 to 10 minutes.

Spoon the meringue over the top of the cooled pie and then spread out using an offset spatula. Create peaks by swirling the spatula and lifting it off. Using a kitchen blowtorch, brown the meringue evenly. Or place under a preheated broiler for about a minute. Cut and serve. Leftovers can be stored in the fridge for up to 2 days. Enjoy!