Chocolate Mayonnaise Cake with Divinity Icing

This simple, moist cake with the “beg your pardon?” ingredient makes a grand companion for sweet, fluffy white icing. A popular pairing in the first half of the twentieth century, this combination of dark chocolate cake with sweet white icing faded away as cooked frostings moved to the back burner and quick confectioners’ sugar frostings tap-danced out to center stage.

The use of mayonnaise in a cake probably began as an economy measure. Its ready-made mixture of eggs and oil offere