Preheat oven to 350 degrees F and grease sheet pan, then line the bottom of the pan with parchment paper and grease and flour the parchment paper.
In a large bowl, sift together 3 cups cake flour, 1 teaspoon baking soda, 1/2 teaspoon salt, and 2 teaspoons unsweetened cocoa powder. Set aside.
In a separate large mixing bowl or stand mixer, cream 1 cup unsalted butter, softened and 1/2 cup vegetable oil for about 3 minutes then add 2 cups sugar. Cream together until light and fluffy.
Add 4 large eggs, room temperature and 1 teaspoon white vinegar and mix until just combined.
Add flour mixture alternately with 1 cup full-fat buttermilk to egg mixture, mixing after each addition. Add 2 teaspoons vanilla extract and 1-2 ounces red food coloring, mixing well.
Pour batter evenly into prepared sheet pan and bake for 20-25 minutes or until done.
For the Frosting
In the bowl of a stand mixer, beat 1 cup unsalted butter, room temperature until creamy. Add 1 8-ounce brick cream cheese, room temperature and beat until mixed with butter and fluffy.
Add 4 cups powdered sugar a little at a time, scraping down the sides and bottom of bowl, beating just until blended. Add 2 teaspoons vanilla extract and salt 1 pinch table saltand mix well.
Cake Assembly
Cut pieces of parchment paper to the size of the mini-cakes to facilitate moving and turning the mini-cakes.
Using an offset spatula assemble the cake cutout circles on top of one another, adding a layer of cream cheese frosting between each. Continue adding layers.
Using your offset spatula, crumb-coat the mini cakes and place in the freezer to set.
Remove from freezer and add a second layer of cream cheese frosting to the sides of the cake. Smooth this second layer with the offset spatula.
Fill piping bag with the remaining cream cheese frosting. Pipe kiss-shaped dots of frosting in a circular pattern on the cake top.