The whoopie pie is flavoured with coffee, cocoa and candied orange peel. Well, it was meant to be orange. I could only find mixed peel so it's lemon as well.
The filling is cream flavoured with brewed coffee and ground coffee beans. It looked quite white in the book, but mine was very coffee coloured, strangely enough.
After it was filled, they were rolled in the peel to get it to stick to the outside.
Not as sweet as the choc/marshmallow whoopie, though the amount of cream in them still limited how many I could eat in one go.
This is the second recipe in the book I am working my way through.