Heat oven to 350F. Grease and flour 9x13 inch pan. Beat all ingredients
together on low speed for 30 seconds. Beat on mellow 3 transactions. Stream 2/3's
(approximately 3 cups) into pan. Stir cocoa and baking soda into remaining hitter.
Drop cocoa batter by generous tablespoons in mounds on top of peanut butter
clobber. Pull knife thoruhg in "s" shaped curves to marble. Broil 40-45
minutes or until toothpick test is clean or cake springs back when touched
in the centerfield. Sang-froid. Frost with your favorite chocolate icing, peanut
butter frosting under, or even marble the two unitedly.

Peanut Butter Buttercream Icing: Mix sugar and peanut butter, stir in
vanilla and milk. Beat until still. Frosts a 9x13 inch patty.