METHOD :
1. Simply cream butter, shortening, and sugar together until light and fluffy then beat in eggs one at a time, making sure to beat well after each addition.
2. Now that you are done beating, mix in vanilla and food coloring then sift together flour, soda, salt, and cocoa.
3. Add to creamed mixture alternately with buttermilk and pour into greased and floured 10-inch tube pan.
4. Afterwards, bake at 350 degrees until cake tests done, about 1 hour.
5. Once done, cool in pan 10 minutes then transfer to serving plate and finally spread with frosting, sprinkle with nuts if desired
