Prepare the Cake: Preheat your oven to 350°F (175°C). Grease and line two 9-inch round cake pans with parchment paper. In a large bowl, sift together 1 ¾ cups all-purpose flour, ¾ cup unsweetened cocoa powder, 2 tsp baking soda, 1 tsp baking powder, and ½ tsp salt. In another bowl, whisk together 2 large eggs, 1 cup buttermilk, ½ cup vegetable oil, and 2 tsp vanilla extract until combined. Gradually combine the wet ingredients with the dry ingredients, mixing until just incorporated. Carefully stir in 1 cup of boiling water until the batter is smooth; it will be thin. Divide the batter evenly between the prepared cake pans and bake for 30 to 35 minutes, or until a toothpick inserted in the center comes out clean.
Make the Raspberry Filling: In a medium saucepan, combine 2 cups of fresh raspberries and ½ cup of granulated sugar. Cook over medium heat, stirring gently until the raspberries release their juices. In a small bowl, dissolve 2 tbsp of cornstarch in 2 tbsp of water, then mix this into the raspberry mixture. Cook for another 5 to 7 minutes, stirring until the filling thickens. If desired, strain the mixture to remove seeds, then let it cool to room temperature.
Prepare the Ganache: In a small saucepan, heat 1 cup of heavy cream until it simmers. Remove from heat and pour the hot cream over 8 oz of finely chopped semi-sweet chocolate in a bowl. Let it sit for 2 minutes to soften the chocolate, then stir until the mixture is smooth and glossy. Allow the ganache to cool slightly until it thickens and becomes spreadable.
Assemble the Cake: Once the cake layers have cooled completely, remove them from the pans. Place one layer on a serving plate and spread a generous amount of the raspberry filling on top. Add the second layer of cake on top of the filling. Pour the chocolate ganache over the top, allowing it to drip down the sides. Decorate with fresh raspberries and chocolate shavings or curls for a beautiful finish.