Preheat oven to 325. In an electric mixer, cream butter and shortening until smooth. Gradually add sugar and beat until light and fluffy, approximately 10 minutes.
Add eggs one at a time, beating well after each addition. Stir in vanilla extract, food coloring, and vinegar, blending well.
Sift flour and baking soda together. Add alternately with buttermilk, beginning and ending with flour mixture. Pour into 2 greased loaf pans (I use glass) Bake at 325 for 1 hour 15 minutes or until loaves test done in center. Cool in pan for 10 minutes before removing cake. Cool completely before glazing.
Glaze-In a bowl place confectioners sugar, milk and cream cheese and mix with hand mixer until blended thoroughly but pourable (may need more milk) I then drizzle all over and back and forth. Let set for 1 hour before slicing.