Chocolate Cake with Toasted Marshmallow Filling

My sister-in-law, Jen, is an amazing cook/baker.  Everything she makes is good.  Our whole family gets excited to see what she is going to bring to our gatherings.

She made this cake for my nephew's birthday and it was DELICIOUS.  The frosting, the filling, the cake...it was all perfection.

Cake:

2 cups flour

2 1/2 cups sugar

3/4 cup unsweetened cocoa powder, preferably Dutch process

2 tsp. baking soda

1 tsp. salt

1 cup vegetable oil

1 cup sour cream

1 1/2 cups water

2 Tbs. white vinegar

1 tsp. vanilla

2 eggs

*Preheat oven to 350 degrees. Butter the bottoms and sides of four 8-inch round cake pans.  Line the bottom of each pan with a round of parchment or waxed paper.  Butter the paper.

*Sift the flour, sugar, cocoa, baking soda and salt in a large bowl.  Whisk to combine.  Add the oil and sour cream and whisk to blend.  Gradually beat in water.  Blend in vinegar and vanilla.  Whisk in eggs and beat until well blended.  Scrape down sides and make sure batter is well mixed.  Divide evenly among the 3 pans.  Bake for 30-35 minutes, or until toothpick inserted comes out clean.  Let cool in pans for 20 minutes.  Invert onto a wire cooling rack, peel off paper liners and let cool completely. (Cakes are very soft so you might want to freeze them for 30 minutes before assembling).

For the Toasted Marshmallow Filling:

16 large marshmallows

1 cup powdered sugar

1 cup unsalted butter, at room temperature

½ teaspoon vanilla extract

1 (7½-ounce) jar Marshmallow Fluff

For the Malted Chocolate Frosting:

2 cups unsalted butter, at room temperature

4 cups powdered sugar

¾ cup Ovaltine Classic

1 tablespoon vanilla extract

Pinch of salt

8 ounces semisweet or dark chocolate chocolate, melted and cooled

½ cup heavy cream

Make the Toasted Marshmallow Filling: Place the marshmallows on a baking sheet lined with aluminum foil and sprayed with nonstick cooking spray. Place on the lowest rack of oven, and broil marshmallows until nice and brown on top, keeping an eye on them the entire time so they don't burn. Remove pan from oven and gently turn the marshmallows over, and broil until the other side is golden brown.

Beat the butter and powdered sugar on low speed until blended together, about 1 minute. Add the vanilla extract and increase the speed to medium-high; beat for 3 minutes. Stop the mixer, add the Marshmallow Fluff and toasted marshmallows, and mix on the lowest speed for about 1 minute, scraping the sides of the bowl as necessary.

Make the Malted Chocolate Frosting: Beat the butter and powdered sugar on low speed until blended together, about 1 minute. Add the Ovaltine, vanilla and salt, and continue to beat on low until well combined, about 1 to 2 minutes. Add the melted chocolate and beat on medium speed until smooth, about 2 minutes. Add the heavy cream and beat on medium-high speed for another minute.

Assemble the cake by layering cake and marshmallow filling and frosting with chocolate frosting.

*Cake recipe from Becoming Betty and frosting/filling recipes from Brown-eyed Baker.