Steven’s chocolate hazelnut sponge with peanut butter frosting cake recipe on The Great British Bake Off 2017 August 29, 2017August 30, 2017admin Steven served up a chocolate hazelnut sponge with peanut butter frosting cake for a salad sandwich illusion on The Great British Bake Off 2017. The Showstopper bake helped Steven to secure the star baker award on the new Channel 4 series.