Preheat oven to 350 degrees F and line cake pans with parchment paper (see instructions here) and coat with cooking spray. Combine all of the cake ingredients in a large bowl or stand mixer fitted with a whisk attachment and beat until combined.
Evenly distribute cake batter between the pans, two 9 in. pans should be for about 30 minutes or until toothpick comes clean. See notes for other sizing and times.
Remove from oven and move the cake pans to the cooling racks to cool.
Once pans are cool enough to touch, gently flip the cakes out and let them cool completely. Put a plate or cooling rack over the top of the pan while flipping.
Prepare the chocolate buttercream recipe.
Cut a 2-inch wide strip from the center of the cake(s) and push the two ends together as shown in the photos above in the post.
On your serving dish, set the cake on two pieces of wax or parchment paper so that the line of the cake is perpendicular to the line where the paper meet.
Frost cake(s) with a frosting spatula. If you're making a layer cake, frost the top of the first layer then add the second and frosting the whole cake. Use a flat ribbon tip to draw on football stitching.