Preheat the oven to 325℉. Place a large roasting pan on the lower third rack of the oven. Place a kettle of water on the stove to boil. Spray a 9-inch springform pan with nonstick spray and line the bottom with a round of parchment paper. Wrap a double layer of heavy duty foil around the bottom and up the sides of the pan.

In a large bowl, use an electric mixer to blend the cream cheese until it is smooth and creamy, 1 to 2 minutes. Mix in the sugar and salt and blend for 2 minutes, scraping down the sides of the bowl to make sure all is mixed in. Add the eggs, one at a time, blending after each addition. Finally, mix in the sour cream, whipping cream and vanilla. Mix until smooth. Pour the batter into the prepared pan.

Set the pan into the roasting pan in the pre-heated oven. Carefully pour the hot water from your kettle into the roasting pan. Pour enough water so that there is about an inch of water coming up the foil along the sides of the cheesecake pan.

Bake the cheesecake for 45 minutes. It should be set to the touch and not jiggly. Remove the cheesecake from the roasting pan and let it cool on a wire rack for at least an hour.

When it has cooled, place the pan into the freezer and let the cheesecake freeze completely (4 to 5 hours or overnight).

Preheat the oven to 350℉. Spray two 9-inch round pans with nonstick spray and line each pan with a round of parchment paper.

In a medium bowl, sift together the flour and salt. In a large bowl, combine the oil and sugar together and beat with an electric mixer for 2 minutes.

Add the eggs, one at a time, and the vanilla, and beat for an additional 2 minutes.

In a small bowl, combine the vinegar and baking soda and stir to dissolve. Add the vinegar to the bowl, along with the buttermilk and food coloring. Beat on medium-low speed for 1 minute, until blended.

Add the dry ingredients and increase speed to medium-high, scraping down the sides of the bowl while mixing, for 2 additional minutes. Divide the batter evenly between the prepared pans.

Bake 30 to 35 minutes, or until a toothpick inserted into the center comes out with a few moist crumbs attached. Let the cakes cool for 20 minutes. Run a knife along the edge of the pans, then invert the cakes onto a rack to cool completely.

In a large bowl, using an electric mixer on medium-high speed, combine the cream cheese and butter and beat until creamy and smooth.

Add the marshmallow creme and mix until smooth. Add in the powdered sugar and continue to beat, scraping down the sides of the bowl, until all of the ingredients are mixed in and the frosting is smooth and spreadable.

Place one cake layer into the center of a cake plate or platter. Remove the cheesecake from the freezer, take off the sides of the pan, and slide a knife under the parchment to remove the cheesecake from the pan. Peel off the parchment.

Trim the cheesecake, as needed to match the size of your cake layers. Place the cheesecake layer on top of the first cake layer. Place the second cake layer on top of the cheesecake.

Apply a crumb coat layer of frosting to the cake, and refrigerate the cake for 30 minutes, or until the frosting is set.

Apply the second layer of frosting. Add a large scoop of frosting onto the top of the cake. Use a long, thin spatula or knife to spread the frosting evenly across the top and then spread it down the sides of the cake too. Decorate, as desired.