Hostess Cupcake Layer Cake

Preheat the oven to 350ºF and prepare three 6-inch or two 8-inch cake pans by spraying the sides with cooking spray and fitting the bottoms with a parchment paper circle.

Place all of the dry ingredients into the bowl of a stand mixer and stir on low for 30 seconds to fully combine them. Add the vegetable oil, eggs, vanilla, and buttermilk and mix on low until just combined. With the mixer still on low, add the hot coffee (or hot water) in a slow stream. Continue mixing on low until fully combined, about 1 minute. The batter will be thin.

Pour the batter into the prepared cake pans and bake for 32-36 minutes, until a wooden toothpick inserted comes out clean. Cool completely before frosting.

Place the chocolate chips into a heat resistant bowl (glass or metal) and set aside. In a saucepan over medium-high heat, warm the heavy whipping cream until it just starts to simmer. I always look for small bubbles forming around the edge and a soft simmer starting in the middle. When it's reached this point, pour the cream into your bowl of chocolate, cover it with a plate, and let it sit for 2 minutes.

Whisk the chocolate and heavy cream mixture together until it’s uniform in consistency and there are no bits of chocolate left on your whisk. Cover the surface of the ganache with a piece of plastic wrap and refrigerate until the ganache is room temperature. This can take between 1-2 hours depending on how deep your bowl of ganache is (the shallower the container the quicker it will set). In the meantime, you can move on to making the marshmallow cream filling if you'd like.

When the ganache ready to whip it will be about the consistency of smooth peanut butter. Use a stand mixer with the whisk attachment or a hand mixer, whip the ganache on medium-high speed just until it lightens in color and maintains a nice peak (similar to the consistency of buttercream frosting), about 2-3 minutes**.

In the bowl of a stand mixer with the paddle attachment or using a hand mixer, whip the butter on high speed until smooth and creamy, about 5 minutes. Turn the mixer to low speed and add the powdered sugar. Mix until fully combined, about 2 minutes.

Add the marshmallow fluff and vanilla. Continue to mix on low speed until combined and uniform, 1-2 minutes.

Once the chocolate cake layers have cooled completely, level and torte each layer to your desired height. Reserve about 2 Tablespoons of marshmallow cream filling (to pipe the top detail) and set aside. Add about 1 Cup of whipped chocolate ganache into a piping bag and snip off about 1/2 inch opening.

Place the first layer on a turntable and pipe a circle of whipped chocolate ganache around the edge of the cake layer. Fill in the center with half of the marshmallow cream filling. Here's a detailed tutorial on this filling method in case this is your first time working with a soft filling.

Place the next cake layer on top and repeat the process of piping the ganache circle and filling in the center with the rest of the marshmallow cream filling. Place the final layer on top, upside down so that the bottom of the cake layer is the top of the cake. Crumb coat the cake with whipped chocolate ganache and place it in the refrigerator for at least 20 minutes to let everything set up.

Use an icing smoother to create a smooth buttercream finish with the rest of the chocolate ganache frosting***, then place the cake into the refrigerator for about 10 minutes to let the frosting set. Add the reserved marshmallow cream filling into a piping bag fitted with Wilton Tip 3. Starting at one edge of the cake, pipe a continuous series of overlapping loops directly across the top of the cake, ending on the opposite edge.