This recipe does take some time but it is so worth it! I made this for a co-worker's birthday and then had someone at work ask me to make it for her husband's birthday. It really is so good! It's not your typical chocolate cake. This recipe comes from pickycook.com.
For Cake Layers
3 oz fine-quality semisweet chocolate
1 1/2 cups hot brewed coffee (or hot water)
3 cups sugar
2 1/2 cups all-purpose flour
1 1/2 unsweetened cocoa powder (It's recommended not to use Dutch processed cocoa but that's what I use from Costco and it seemed to be just fine to me)
2 tsp baking soda
1 tsp baking powder
1 1/4 tsp salt
3 large eggs
3/4 cup vegetable oil
1 1/2 cups well-shaken buttermilk
3/4 tsp vanilla
For Ganache Frosting
1/2 pound fine-quality semisweet chocolate
1/2 cup heavy cream
1 Tbsp sugar
1 Tbsp light corn syrup
2 Tbsp unsalted butter
Make Cake Layers
Preheat oven to 300 F and butter pans 2 - 10 inch round baking pans (It says you can use 9 inch but when I did that it overflowed in my oven. If you have the professional ones with the tall sides it would be ok). Line bottoms with rounds of parchment paper. Butter again and dust both pans with cocoa powder. Tap and swirl around the cocoa to lightly coat the pans.
Finely chop chocolate and in a bowl combine with hot coffee (or water). let mixture stand, stirring occasionally, until chocolate is melted and mixture is smooth.
Into a large bowl sift together sugar, flour, cocoa powder, baking soda, baking powder, and salt. In another large bowl with an electric mixer beat eggs until thickened slightly and lemon colored (about 3 mins) Slowly add oil, buttermilk, vanilla, and melted chocolate mixture to eggs, beating until combined well. Add sugar mixture and beat on medium speed until just combined well.
Divide batter between pans and bake in middle of oven until a tester inserted in center comes out clean. 1 hour to 1 hour and 10 mins.
cool layers completely in pans on racks. Run a thin knife around edges of pans and invert layers onto racks. Carefully remove parchment paper and cool layers completely. Cake layers may be made 1 day ahead and kept, wrapped well in plastic wrap, at room temperature.
Ganache Frosting
Finely chop chocolate. In a small saucepan bring cream, sugar, and corn syrup to a boil over moderately low heat, whisking until sugar is dissolved. Remove pan from heat and add chocolate, whisking until chocolate is melted. Cut butter into pieces and add to frosting, whisking until smooth.
Transfer frosting to a bowl and cool, stirring occasionally , until spreadable.
Raspberry Filling
2 10-ounce bag frozen raspberries, thawed
1/2 cup sugar
zest of 1 lemon
Tbsp cornstarch
Puree the raspberries in a food processor. Press the puree through a fine-mesh strainer with the back of a spoon, removing the seeds. Heat the puree in a small pot with the sugar and cornstarch until mixture boils, stirring constantly. As it boils, it should quickly thicken. Stir in lemon zest at the end.
Let it cool complete before spreading it thinly over three layers.
To Assemble
With a long serrated knife, slice each cake into two layers. Lay the bottom layer on cake stand. Take 1/3 the raspberry filling and spread it over the layer. Stay about 1/2 inch away from the edge. lay the next layer on top.Spread another 1/3 of the raspberry filling. place the third layer on cake and the last of the raspberry filling. Put the final layer on the top of the cake. Gently make sure that all the layers line up.
Pour some of the ganache in the middle of the top layer and with an offset spatula start smoothing out the frosting - gently pushing it toward the edge. Add more until you have worked the ganache down over the sides of the cake.
Decorate with fresh raspberries if you would like.