Honestly, I rather expected this book to go into some of the more unusual items of food within the wizarding world, such as fizzing whizzbees, cockroach clusters or even the ubiquitous butterbeer. What I actually received was a cookbook full of basic British recipes, ill-researched and clearly marketed heavily towards a market which was more enamoured with the "British-ness" of Harry Potter than the magical elements.
Many of the recipes would be far more difficult to follow than others I have seen, and often produced much poorer results.
Honestly, if you were unfamiliar with many of the recipes in the Harry Potter world, then I guess this book is a decent enough introduction to European/British cuisine, but if you hail from the UK, I would say AVOID. Go grab a Beero or Delia Smith book instead, you'll yield far better results!