Wacky Cake is unique in that, unlike most pastries and desserts, no eggs, butter or milk are used to make the cake batter. It is commonly believed that Wacky Cake may have been created as the result of rationing during World War II, when milk and eggs were scarce. Active ingredients in wacky cake include flour, sugar, cocoa powder, baking soda, vegetable oil, white vinegar and vanilla extract.