Preheat the oven to 375°. Butter and flour a 15-by-10 1/2-inch jelly roll pan; tap out excess flour. Place a large piece of parchment in the pan, allowing the excess to drape over the long sides of the pan.
In 2 large bowls, separate the egg yolks from the whites. Using an electric mixer on medium-high speed, beat the egg yolks and sugar until pale, about 3 minutes. Add the milk and beat on medium speed to blend. Sift in 3/4 cup flour, the cocoa powder, baking powder and salt. Beat on low speed, stopping once to scrape down the sides of the bowl, until blended, about 1 minute. Wash and dry the beaters. Beat the egg whites on medium speed until soft peaks form, 2 to 3 minutes; add to the batter and fold just to blend. Pour the batter into the prepared pan; spread out in an even layer. Bake until the cake springs back when touched in the center, about 12 minutes. Let cool in the pan on a wire rack for 15 minutes.
Meanwhile, for the filling, in a medium saucepan, cook the Mounds bars, sweetened condensed milk, sugar, butter, vanilla and salt over medium-high heat, stirring often, until melted, 3 to 4 minutes. Let the filling cool slightly.
Invert the cooled cake onto a large sheet of parchment paper. Peel off the parchment from the bottom of the cake. Spread with the marshmallow crème, leaving a 1/2-inch border around the edges of the cake. Pour the melted candy bar mixture over the marshmallow crème, spreading to cover. Using the parchment paper as an aid and starting from one short side of the cake, roll the cake into a log. Let cool completely.
For the toppings, in a small pot, bring the cream to a simmer over medium-high heat. Remove from heat, add the chocolate chips and stir until smooth. Let the glaze cool and thicken slightly, about 5 minutes. Using a serrated knife, trim the edges of the cake roll to create clean sides. Pour the glaze over the cake and dust with the cocoa powder.
Top with the chopped Mounds bars, toasted almonds and toasted coconut.
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