1Preheat the oven to 350 degrees. Butter and flour three 8 inch cake pans, and line the bottoms with parchment paper. Butter and flour the parchment; set aside.
2Place flour, sugar, baking soda, salt and cocoa powder in a large mixing bowl. Using an electric mixer, mix on low to combine. Keep the mixer on low and add oil, buttermilk, then eggs one at a time. Add hot coffee in a thin stream, pouring down the side of the bowl. Add vanilla and mix until batter is smooth.
3Divide into pans and bake until a toothpick comes out with moist crumbs, about 30-35 minutes. Let cool in pans for 10 minutes.
4To make frosting:
Whip together the mascarpone, vanilla seeds, salt, and sugar. Gradually add the whipped cream into the cheese mixture. Whip until lightand creamy. Frost the cake completely, and place in the refrigerator to chill for about 30 minutes while you make the ganache.
5To make ganache:
Put the chocolate in a medium bowl. Set aside. In a small saucepan over medium low heat, heat the cream until it is hot and just beginning to bubble. Remove from heat and pour over the chocolate, stirring until the chocolate is completely melted. Add corn syrup and vanilla, stirring until completely mixed. Pour the chocolate mixture into a liquid measuring cup with a pouring spout and let chocolate glaze cool for 10 minutes. Do not let the glaze sit longer than 10 minutes because it will thicken and become difficult to pour over the cake. Slowly pour the glaze over the cake. Cover the top of the cake entirely, letting some of the glaze drizzle down the sides, and allowing some of the whipped cream show through the drizzles around the side of the cake.
Chill 4 hours before serving. Store cake in the refrigerator.