2 1/2 cups all-purpose flour
1 1/2 cups sugar
1 tsp. baking soda
1 tsp. salt
1 tbsp. cocoa powder
1 1/2 cups canola oil
1 cup buttermilk
1 – 1 oz. bottle red food coloring
1 tsp. vanilla bean paste
In the bowl of an electric mixer with paddle attachment combine flour, sugar, baking soda, salt, cocoa powder and oil. Turn mixer on medium and mix until well combined – then add buttermilk, eggs, red food coloring, vinegar and vanilla bean paste. Turn mixer on low and mix for 2-3 minutes until completely incorporated. Scrape bowl with a spatula if necessary to make sure all of the ingredients are combined.
Prep two 9? square cake pans by spraying them with Bak-klene and placing parchment in the bottom. Divide the batter in half between the two pans, and bake them off in a preheated 325 degree oven for 25-30 minutes. Remove from the oven and allow to rest in the pan for ten minutes, then invert onto a cooling rack to finish cooling completely.
In a liquid measuring cup, place 1/2 c. heavy cream and a 10 oz. bittersweet chocolate bar that has broken up in to the microwave and heat in 30 second intervals, stirring in between until chocolate is melted. Allow mixture to cool until thickened enough so it's spreadable, yet doesn't run all over like water. This will get you the drips on the edge of the cake. Set aside to cool.
You will need 4 c. of heavy whipping cream. In a small sauce pan place 1 package unflavored gelatin and 1/3 c. heavy cream, please heat setting to medium and cook mixture, stirring regularly until it begins to bubble. Remove from heat and pour into a mixing bowl, mixer fitted with the whisk attachment. Pour remaining heavy cream into mixer and turn on, slowly turning the speed level up to high, whipping until cream has stiff peaks. Add 1 1/2 c. powdered sugar and 1 tbsp. vanilla bean paste, then whip again to combine.
You can either spread whipped cream on the layers using a spatula, or pipe them on as I did using a large star tip. The whipped cream is stabilized with the gelatin, so it will not weep on you.