Preheat oven to 300 degrees.
Grease and flour cake pans.
Cream sugar and shortening in large mixing bowl until fluffy.
Continue to mix slowly and add eggs one at a time.
Whip until mixture is light and fluffy.
In small mixing bowl, make a paste of cocoa and food coloring.
Add to creamed mixture, whipping again until light and fluffy.
Sift flour and salt together.
Mixing batter, slowly add flour mixture alternately with buttermilk and vanilla.
Mix until smooth and fluffy!
Continue mixing slowly and sprinkle soda on top of batter and fold in.
Fold in vinegar, then whip batter until light and fluffy.
Fill pans and bake 30 to 40 minutes until done.
Cool 10 minutes before removing from pan.