Directions

• Chocolate Cake:
• Heat oven to 350℉.
• Combine the butter and sugars in the bowl of a stand mixer fitted with the paddle attachment and cream together on medium-high for 2 to 3 minutes. Scrape down the sides of the bowl, add the eggs, and mix on medium-high for 2 to 3 minutes. Scrape down the sides of the bowl once more.
• On low speed, stream in the buttermilk, oil, and vanilla. Increase the mixer speed to medium-high and paddle for 4 to 6 minutes, until the mixture is much lighter in color, twice the size of your original fluffy butter-and-sugar mixture, and completely homogeneous. Don’t rush the process. You’re basically forcing too much liquid into an already fatty mixture that doesn’t want to make room for the liquid. There should be no streaks of fat or liquid. Stop the mixer and scrape down the sides of the bowl.
• On low speed, add the cake flour, cocoa powder, baking powder, and salt. Mix for 45 to 60 seconds, just until your batter comes together and any remnants of dry ingredients have been incorporated. Scrape down the sides of the bowl.
• Pam-spray a quarter sheet pan and line it with parchment, or just line the pan with a silpat. Using a spatula, spread the cake batter in an even layer in the pan. Give the bottom of your cake pan a tap on the countertop to even out the layer.
• Bake the cake for 30-35 minutes. The cake will rise and puff, rising to the top of the sheet pan. At 30 minutes, gently poke the edge of the cake with your finger: The cake should bounce back slightly and the center should no longer be jiggly. Leave the cake in the oven for an extra 3 to 5 minutes if it doesn’t pass these tests.
• Take the cake out of the oven and cool on a wire rack or, in a pinch, in the fridge or freezer (don’t worry, it’s not cheating). The cooled cake can be stored in the fridge, wrapped in plastic wrap, for up to 5 days.
• Malt Fudge Sauce:
• Combine the chocolate, ovaltine, and salt in medium bowl.
• Combine the glucose, molasses, sugar, and heavy cream in a heavy-bottomed saucepan and stir intermittently while bringing to a boil over high heat. The moment it boils, pour it into the bowl holding the chocolate. Let sit for 1 full minute.
• ​Slowly, slowly begin to whisk the mixture. then continue, increasingly the vigor of your whisking every 30 seconds, until the mixture is glossy and silky-smooth. This will take 2 to 4 minutes, depending on your speed and strength. You can use this sauce at this point or store it in an airtight container in the fridge for up to 2 weeks; do not freeze.
• Chocolate Malt Frosting:
• Combine the butter, sugar, salt, and cocoa powder and ovaltine in the bowl of a stand mixer fitted with the paddle attachment and cream together on medium-high for 5 to 7 minutes, until the mixture is smooth and fluffy. Scrape down the sides of the bowl.
• With the mixer on its lowest speed, stream in the milk. crank the mixer up to medium-high and beat for 2 to 3 minutes, until the mixture is silky smooth and a glossy. Scrape down the sides of the bowl. Use the frosting immediately, or store it in an airtight container in the fridge for up to 1 week.
• Malt Crumb:
• Heat the oven to 250°F.
• Combine the  ⅓ cup milk powder, the flour, cornstarch, 1/4 cup of ovaltine, sugar, and salt in a medium bowl. Toss with your hands to mix. Add the melted butter and toss, using a spatula, until the mixture starts to come together and form small clusters.
• Spread the clusters on a parchment- or silpat-lined sheet pan and bake for 20 minutes. The crumbs should be sandy at that point, and your kitchen should smell like buttery heaven. Cool the crumbs completely.
• Crumble any milk crumb clusters that are larger than ½ inch in diameter, and put the crumbs in a medium bowl. Combine the 3 tbsp of ovaltine and milk powder and toss together with crumbs until it is evenly distributed throughout the mixture.
• ​Pour the white chocolate over the crumbs and toss until your clusters are enrobed. Then continue tossing them every 5 minutes until the white chocolate hardens and the clusters are no longer sticky. The crumbs will keep in an airtight container in the fridge or freezer for up to 1 month.
• Ovaltine Soak:
• Whisk together milk and Ovaltine™ in a small bowl until the Ovaltine™ is completely dissolved. use immediately.
• Charred Marshmallows:
• Spread the marshmallows out evenly on an unlined sheet pan and char them to hell and back with a blowtorch. Transfer the pan to the fridge or freezer for 10 minutes to firm up and make them easier to handle. Use immediately or store in an airtight container at room temperature for up to 1 week.
• Cake Assembly:
• Put a piece of parchment or a silpat on the counter. Invert the cake onto it and peel off the parchment or silpat from the bottom of the cake. Use the cake ring to stamp out 2 circles from the cake. These are your top 2 cake layers. The remaining cake “scrap” will come together to make the bottom layer of the cake.
• Clean the cake ring and place it in the center of a sheet pan lined with clean parchment or a silpat. Use 1 strip of acetate to line the inside of the cake ring.
• Put the cake scraps together inside the ring and use the back of your hand to tamp the scraps together into a flat even layer.
• Dunk a pastry brush in the Ovaltine soak and give the layer of cake a good, healthy bath of half of the soak.
• Use the back of a spoon to spread one-third of the malt fudge sauce in an even layer over the cake. (Helpful hint: the warmer the fudge sauce, the easier it is to spread.)
• Sprinkle one-third of the malted milk crumbs and one-third of the charred marshmallows evenly over the malt fudge sauce. Use the back of your hand to anchor them in place.
• Use the back of a spoon to spread one-third of the malt frosting as evenly as possible over the crumbs and marshmallows.
• With your index finger, gently tuck the second strip of acetate between the cake ring and the top ¼ inch of the first strip of acetate, so that you have a clear ring of acetate 5 to 6 inches tall – high enough to support the height of the finished cake. Set a cake round on top of the frosting, and repeat the process for layer 1 (if 1 of your 2 cake rounds is jankier than the other, use it here in the middle and save the prettier one for the top).
• Nestle the remaining cake round into the frosting. Cover the top of the cake with the remaining frosting. Garnish with the remaining charred marshmallows.
• Transfer the sheet pan to the freezer and freeze for a minimum of 12 hours to set The cake and filling. the cake will keep in the freezer for up to 2 weeks.
• At least 3 hours before you are ready to serve the cake, pull the sheet pan out of the freezer and, using your fingers and thumbs, pop the cake out of the cake ring. Gently peel off the acetate, and transfer the cake to a platter or cake stand. Let it defrost in the fridge for a minimum of 3 hours (wrapped well in plastic, the cake can be refrigerated for up to 5 days). Slice the cake into wedges and serve.