Pre-heat oven to 350.
Butter and flour 2 9" round pans or a 9x13 in pan. In large bowl cream together your sugar and shortening, add food coloring, eggs and vanilla.
In another bowl sift together your flour, cocoa and salt.
Alternate adding your flour mix and buttermilk to your sugar mix and beat until smooth.
In small bowl mix together your baking soda and vinegar and add to your batter.
Spread batter into desired cake pan and bake for 30 minutes or until center is set and toothpick comes out clean.
Meanwhile to make frosting, in small saucepan on stove mix together your milk and flour and cook on medium until thick.
Set aside to cool.
In large bowl cream together your sugar and shortening until light and fluffy.
Add your cooled milk mixture and continue beating until fluffy again.
Stir in your vanilla. Spread onto cake, top with coconut and serve!