Preheat the oven to 350 degrees F (180 degrees C). Line a 13x9 inch baking pan aluminum foil.
With a whisk attachment on a standing mixer or using a hand mixer and a large bowl, mix the Egg (6) and Granulated Sugar (1 cup) on medium speed until light and fluffy, about 5 minutes.
Add the Sour Cream (1 1/2 cup). Dissolve the Baking Soda (1 1/2 teaspoon) in Distilled White Vinegar (1 teaspoon) and also add to the cake batter. Mix to combine.
Add the All-Purpose Flour (1 1/2 cup) and mix until incorporated. The batter will still be on the thinner side.
Pour into prepared baking dish.
Bake for about 30 minutes until cake springs back to the touch and a toothpick comes out clean.
Cool slightly, just until you can handle it. Tear the cake into pieces. This is the fun part! The cake should be almost cool when you're done tearing it apart, but if it isn't, just set aside until it's completely cool.
Meanwhile, make the frosting. With a paddle attachment on a standing mixer or using a hand mixer, mix the Cream Cheese (8 ounce) until it has a creamy and even consistency.
Add the Sweetened Condensed Milk (1 can). Mix to combine. Add the Sour Cream (1 tub) and Vanilla Extract (2 teaspoon) and also mix to combine.
In another chilled bowl with a chilled whisk attachment, whip the Heavy Cream (1 cup) until stiff but still somewhat soft peaks form.
Gently fold the whipped cream into the rest of the frosting with a rubber spatula. When the cake is cool, pour in part of the frosting and mix.
Keep adding more frosting until all of the cake is completely covered in frosting, but don't add too much or the cake will be mushy. Set aside the remaining frosting to spread over the assembled cake. Add the Fresh Raspberries (1 pint) and VERY GENTLY mix to combine.
You can form the cake into any shape that you like – circle, square, etc. You can also use the sides of a springform pan to help you shape it, by placing the rim on top of the serving plate, putting the cake inside the springform and then taking the springform off.
Cover with the remaining frosting and decorate with chocolate shavings, chocolate glaze, berries, nuts or whatever else you like.