In a bowl, whip the heavy whipping cream with a mixer on mdeium spead until cream thickens. Turn speed to high and beat until soft peaks form, about 2-3 minutes. Don’t OVERBEAT.
Once heavy whipping cream is beaten, add sour cream and sugar. Mix on low speed just until sugar is well incorporated. Set aside.
In a saucepan, add the cold milk and spinkle gelantin over the milk, let sit for about 2-4 minutes.
Place on a stove top. Continuously mixing, let the gelatin completely melt and get very warm, NOT hot and do NOT boil.
Pour milk into the bowl with the rest of the ingredients and with a spatula mix until everything is combine.
Place in refrigerator for half an hour to an hour. Mousse should completely thicken before adding chocolate layer.
Chocolate Layer-
In a bowl, combine the sugar, gelatin, and cocoa. Combine the half and half with water. Pour the mixture to the chocolate mixture.
Place onto the stove top. Keep mixing until everything becomes very warm, do not boil. Remove from heat and let cool completely before adding to mousse.
Since the mousse was refrigerated and is cold when the chocolate layer is poured, it will thicken on contact, pour quickly and spread evenly atop the mouse. Pour chocolate into the middle and spread. Finish one cup then go to the next. Refrigerate for at least three hours or overnight. Add raspberries before serving.