Preheat oven to 350°F. Spray 3 (8" round) cake pans with non-stick cooking spray. Line with parchment paper and spray again. Set aside.

In a medium bowl, whisk together flour, cocoa, soda and salt. Set aside.

In a large bowl, beat butter and sugar with an electric mixer on medium until light and fluffy (about 3 minutes). Reduce mixer speed to low and add eggs, then liqueur. Keep mixing on low until combined. Then gradually add flour mixture, milk and sour cream. Keep mixing on low until just combined. Do not overmix. Stir in the melted chocolate, then pour batter into prepared pans. Smooth the batter with an offset spatula. Bake for 25 minutes or until a toothpick inserted into middle of cake comes out clean. Let cakes cool in pans.

In a medium saucepan, place frozen raspberries, sugar, lemon juice and water/cornstarch mixture. Let the mixture come to a bowl over medium high, stirring constantly. Continue to boil for one minute or until slightly thickened. Remove from heat then press mixture through a strainer to get the seeds out. Stir in liqueur. Let cool.

Place chocolate chips in a heatproof bowl (I used a glass bowl). Pour cream into a saucepan and let it come to a boil over medium heat. Once it's boiling, remove from heat and pour over chocolate chips. Cover bowl with plastic wrap and let it sit for about 15 minutes. Stir until completely melted and combined. Let it cool completely. You can speed up the process by putting it in the fridge, but watch it carefully because it can get hard if it's too cold.

To assemble cake, place one cake layer on a serving platter or cake plate. Spread half of the raspberry filling onto layer. Add second cake and do the same thing. Add the third cake layer on top. Frost top and sides of cake with the cooled chocolate ganache frosting. Decorate with fresh raspberries.

Serve immediately or store covered for up to one day. After that store covered in the refrigerator for several days.