Preheat oven to 350 degrees. Prepare two 8" pans with nonstick spray and parchment paper - I use square pans
In a small bowl mix the cocoa powder and red food coloring together and set aside.
In a large bowl beat the shortening and sugar together until fluffy.
In another bowl mix the eggs, buttermilk, vanilla,
To the bowl of shortening and sugar, add the flour and buttermilk mixture alternating between the two. Mix well after each addition. Add the salt
Pour the cocoa powder mixture into the bowl and mix until combined.
In a small bowl mix the vinegar and baking soda, then mix into the batter until combined.
Pour the batter between the two baking pans. Bake for 25 minutes or until a toothpick comes out clean. Let cool on racks for before removing from pans.