Preheat oven to 350°F. Lightly oil and flour three 9 by 1 1/2-inch round cake pans.
In a large bowl, beat the egg whites until soft peaks form (about 2 minutes) and set aside. Whisk cake flour, baking soda, cocoa powder, and salt. Set aside.
Using a hand or stand mixer, beat the butter and sugar until creamy and light. Add oil, vanilla, egg yolks, vinegar, and food coloring. Alternate adding flour and buttermilk. Fold in egg whites gently.
Divide the cake batter evenly among the prepared cake pans. Bake for approximately 25 minutes or until a toothpick inserted into the center of one comes out clean.
For Frosting: Beat butter and cream cheese with vanilla. Add powdered sugar. Beat 5-7 minutes. Frost cake, then refrigerate to set.
Notes: If desired, you can add chopped pecans between layers and on top of the cake.