I sat cross-legged on the carpeted floor of my rented canalhouse apartment in Amsterdam, hunched over my neatly packed suitcase. Every item had appeared to be in its place, perfectly rolled and folded. And then I saw a rogue sprinkle. I gingerly plucked the offending confection off my shirt, careful not to streak the fabric with chocolate, and popped it into my mouth. No sense in wasting a good sprinkle.
I dug a little deeper. I found a pocket of four more and ate them one by one. Then another little reservoir. Then another. The box of dark chocolate De Ruijter sprinkles that I had planned to cart back to the States had sprung a tiny leak. Little pockets of sprinkles were sprinkled in every pocket of my suitcase. As I tracked them through my luggage, I imagined myself a contented chimpanzee at mealtime, carefully digging for ants. I searched with deliberate intensity for precious sustenance that I discovered only in tiny but triumphant increments. Try it in your kitchen after you decorate this cake.
To evenly apply sprinkles onto a frosted cake, place the cake on a cake stand set in a rimmed baking sheet. Pour the sprinkles into your hand, aim at the cake, and blow gently. Make a wish. Rotate and repeat.
This cake is killer the next day, zapped for a few seconds in the microwave and served with a big glass of milk. (Eat while wearing pajamas, either for breakfast or a midnight snack.)
Prepare the cake: Preheat the oven to 350°F. Butter two 9-inch round cake pans and line with parchment. Butter the parchment.
In a large bowl, whisk together the cocoa powder and the boiling water until smooth. Add the sour cream and coffee. Add the oil, eggs, and brown sugar and whisk until smooth. In a medium bowl, whisk together the flour, malted milk powder, baking powder, baking soda, and salt. Fold the dry ingredients into the wet ingredients.
Divide the batter between the prepared pans and bake until a toothpick inserted into the center comes out with moist crumbs attached, 35 to 40 minutes. Transfer the pans to a wire rack to cool lightly. Remove the cakes from the pans and transfer to the rack to cool completely.
Prepare the frosting: In a small saucepan, whisk together the cream and malted milk powder and bring to a simmer over medium-high heat. Place the chocolate in a heatproof bowl. Pour the cream mixture over chocolate and let stand for 1 minute. Whisk the chocolate mixture until smooth. Whisk in the butter and salt.
Let the frosting stand at room temperature until smooth and spreadable, stirring occasionally, about 1 hour.
Trim the cakes so that they are flat. Transfer a cake layer to a serving plate, trimmed-side up. Top with about 1 cup of frosting. Top with the second cake layer, flat-side up, and cover the cake with the remaining frosting. Sprinkle liberally with sprinkles.