Preheat the oven to 325 degrees F. Place a 13x9 pan on the lower third rack of the oven and fill it halfway with water. Place another rack on a level above the pan. Spray a 9-inch springform pan with nonstick spray.

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 on the rack above the roasting pan. Bake the cheesecake for 40 to 45 minutes.

Remove the cheesecake from the oven 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 degrees F, and spray two 9-inch pans with nonstick spray with flour (baking spray). In a large bowl, whisk together the flour, sugar, baking powder and salt.

Add the eggs, buttermilk, butter, shortening, zest, and juice to the bowl. Use an electric mixer on low speed to combine (1 minute). Scrape sides and bottom of the bowl with a rubber spatula. Beat on high speed 2 minutes.

Add the soda and vanilla and beat on low speed for 30 seconds until incorporated. Divide the batter between the two prepared pans. Bake 25 to 30 minutes, or until a toothpick inserted into the center comes out with just a few moist crumbs attached.

Let the pans cool on a wire rack for about 20 minutes, then run a knife around the edges of the pans and turn the cake layers onto rack to cool completely.

In a large bowl, use an electric mixer on high speed to beat the cream cheese and butter until creamy. Gradually add the powdered sugar, beating on low speed until blended.

Scrape down the bowl with a rubber spatula. Add the lemon zest and ¼ cup lemon juice; beat on high speed for 1 to 2 minutes or until fluffy.

If the frosting appears to be too thick, add an additional tablespoon or two until you get a nice consistency. Cover and refrigerate the frosting until you are ready to assemble the cake.

Place one cake layer into the center of a cake plate or platter. Spread a couple of spoonfuls of frosting on top.

Remove the cheesecake from the freezer, take off the sides of the pan, and slide a knife under the the cheesecake to release it from the pan. Trim the cheesecake, as needed to match the size of your cake layers.

Place the cheesecake layer on top of the first cake layer and spread a couple more teaspoons of frosting on top of the cheesecake.

Place the second cake layer on top of the cheesecake. Pile the frosting on top of the 2nd cake layer, spread it to the edges and down the sides of the cake.

Decorate as you wish! Keep this cake refrigerated until serving. It's okay to make it 24 hours in advance and keep it in the refrigerator.