6ouncebittersweet chocolate (60% cacoa), broken into squares
1 1/4cupsheavy cream
1tablespoonlight corn syrup
Place butter, chocolate, sugar, heavy cream, and corn syrup in a medium-sized pan over medium heat. Stir frequently.
When the mixture comes to a boil, give it a good stir and then let it boil without stirring for 1 minute.
Remove from heat. Stir in the vanilla extract.
Set aside, uncovered, and allow to cool for 1-2 hours.
Preheat oven to 350 degrees. Spray 9-inch cake pans with non-stick cooking spray. Line with parchment paper circles and spray again.
Using a handheld or stand mixer, combine cake mix, milk, butter, and eggs on low speed for 30 seconds. Scrape the sides.Increase speed to medium-high and continue beating for 2 minutes.
Use a 1-cup measuring scoop to remove slightly less than a cup of cake batter. Pour this small amount of cake batter into a parchment-lined cake pan. Repeat to fill as many cake pans as you have.Bake for 10-12 minutes, or until a toothpick inserted comes out clean.Remove from oven and let cool for 5 minutes, then invert onto a cooling rack. (See FAQ notes for tips on cooling and stacking.)
Grease pans and place a parchment circle inside. It is okay to reuse the parchment circles, as long as you grease/spray them each time. Repeat the above steps, filling each cake pan with just under a cup of batter, and baking, until all of the cake layers have been baked.Cool cakes completely.
Assembling the Cake
Place the first layer of cake onto a serving plate or cake stand. Tear off 4 strips of parchment paper, each about 2-inches long (as wide as your roll - do not cut). Tuck a strip of parchment about a half-inch under each side of the cake, so that the paper will catch any frosting that drips down. This will help your serving plate stay clean.
Spread 1/4 cup of frosting over the top of your first layer. Stack the next cake layer on top of the first, and top with 1/4 cup of frosting. Repeat with each layer.Pour remaining frosting over the top of the cake and onto sides.
Remove parchment strips. Place the cake in the refrigerator for at least 30 minutes, so that the frosting sets up. If the cake is refrigerated for longer than 2 hours, remove from the refrigerator 30 minutes prior to serving.
Cover leftover cake and store at room temperature for 2 days, or in the refrigerator for up to 5 days.
The nutritional facts provided are only estimates. The accuracy of the nutritional information for any recipe on this site is not guaranteed.