This recipe is from Shirley McNevich's Mom's Best Recipes Vol 1. Published here with her permission.
Don't forget to check Shirley's blog.
(by Shirley McNevich)
2 cups sugar (1 white, 1 dark brown--Domino Brand)
1/2 cup Parkay Margarine (1 stick)
1/2 cup Hershey Cocoa
1 TBSP vanilla
Pinch of salt
1 TBSP baking soda (Arm & Hammer brand)
1 cup buttermilk (or powdered buttermilk--follow directions on label to equal 1 cup buttermilk)
2 cups sifted flour (measure flour before you sift it!)
1/2 cup boiling water
1 cup coarsely crushed Oreo cookies
Vanilla frosting (ingredients listed after recipe)
Beat Parkay margarine and sugar until creamy. Add eggs, vanilla, salt, and cocoa. Mix baking soda in buttermilk until it starts to fizz. Pour buttermilk into batter. Stop mixer and add flour. Mix until smooth, about 3 minutes. Add boiling water and mix. In a Ziploc bag, coarsely crush Oreo cookies until you have enough for 1 cup--take out 3 TBSP of crushed Oreo cookies to use later in the frosting. Stir the rest of the 1 cup crushed Oreo cookies into the cake batter. Pour batter into long cake pan 13 by 9 by 2. Bake at 375 degrees for 35 minutes. Test if it's done using a toothpick. If toothpick comes out clean, it's done. If it doesn't come out clean, leave in a few more minutes and retest. Frosting: 1/2 box Domino's Powdered Sugar (1 lb. size); 1 stick Parkay margarine; 2 tsp. imitation vanilla; 1.5 TBSP milk. Feed in mixer. The longer you beat it the creamier it gets. When finished making frosting, stir in the 3 TBSP of crushed Oreos that you had set aside. Frost cake when it is cool. You can add more crushed Oreos to the top for decoration if you wish.