This Giant Hostess Cupcake Cake is three chocolate cake layers with a cream-filled center and rich ganache frosting. It's a great all-purpose cake for nearly any special occasion. Save the cut-out cake centers. You'll have a little leftover cream filling and can assemble your own personal-sized mini cake with the scraps and leftovers.
1/2cupegg whitesabout 2 1/2 egg whites, I used carton egg whites
1/4teaspooncream of tartar
3/4cupplus 2 tablespoons granulated sugar
Confectioners’ glaze for décor
1/2cupconfectioners’ sugarplus more if needed
1-2teaspoonsof milk or creamplus more if needed
Preheat the oven to 350F. Grease three 8-inch round cake pans with flour-based baking spray.
Combine the dark cocoa powder and hot water in a small bowl and whisk together until smooth and dissolved. Set aside.
In the bowl of an electric stand mixer, combine the butter and sugar until light and fluffy. Mix in eggs one at a time. Scrape down the bowl and mix again. To the creamed mixture add the baking soda, salt and baking powder. Mix again briefly.
In a 4 cup or larger glass measure with a pour spout, combine the dissolved cocoa mixture and buttermilk. Whisk until combined.
Mix in the flour in three additions, alternating with the buttermilk/cocoa mixture (Order: 1/3 of the flour, 1/2 the liquid, 1/3 flour, remaining liquid, remaining 1/3 flour). Mix on low speed until each is incorporated.
Bake for 30-35 minutes or until a toothpick tester inserted near the center comes out clean. Cool cakes in the pans for 5 minutes, then turn out to cool completely on wire racks. When cakes are cool, cut out and remove a 3.5 inch circle from two of the cakes. Save cake scraps for snacks, cake pops, or for a quick hot fudge sundae.
Pour the chocolate chips in a large microwave-safe bowl. Add the cream and tamp the chips down into the cream so they are all covered. Microwave at 100% power for 2 minutes. Let mixture stand for 1 minute then whisk together until a shiny, thick ganache is formed. Transfer to the refrigerator to firm. Stir ganache intermittently until mixture is of soft spreading consistency, like buttercream, which should take about 20-30 minutes.
Bring a pot with 2 inches of water to a simmer. Place egg whites, cream of tartar and sugar into a stainless-steel mixing bowl and whisk to combine. Set the bowl on top of the simmering water and whisk constantly until the mixture is hot and sugar is dissolved. Check by rubbing a little of the mixture between your fingers. If the mixture is still grainy, keep whisking and cooking. Mixture is ready when the sugar is melted and an instant-read thermometer registers 160F.
Remove the bowl from the simmering water and pour into an electric stand mixer fitted with the whip attachment. Beat for 5-7 minutes on medium high until the mixture is thick and billowy, and holds stiff peaks. Beat in the vanilla extract.
Place a cake layer with a hole in the center on a cake board or server. Frost top edges with ganache. Top with the second cake layer with a hole in the center. Frost top with ganache. Pour cream filling into the center, filling the hole all the way to the top of the hole (You will have a little cream filling left over). Top with the final cake layer without a hole. Frost the entire cake with a crumb coat of ganache. Refrigerate until firm, about 15 minutes.
Ganache will set, so re-heat, if necessary, in the microwave for 15-20 seconds, or until loosened. Remove cake from the refrigerator and apply a second thick coat of ganache.
Mix the confectioners’ sugar and 1 teaspoon of milk in a small bowl. Whisk together until a very thick paste is formed. It should hold in the balloon of the whisk and very slowly fall out. Use more or less of each of the sugar and milk to reach this correct consistency. Remove to a piping bag or zip-top bag with a small hole snipped in the corner. Pipe a series of consecutive loops on top of the cake in Hostess Cupcake fashion.
Serve slices of cake on their sides instead of standing upright. The filling will fall out of the cake slices otherwise. Serve with ice cold glasses of milk for an extra dose of childhood nostalgia.
Cover cake leftovers with plastic wrap. Store in the refrigerator. Bring to room temperature before serving.
If you're not using carton egg whites as I did, beat three whole egg whites lightly in a bowl, then pour into a 1/2 cup measure.