The book I am reading is called "This book is not good for you".  The book is written by Pseudonymous Bosch.  There are 3 protagonists and there names are Cassandra Cass for short then Max Ernest and Yo-Yoji they are Cass and Max are 11 and Yo-Yoji is 12.  The story is about the perfect chocolate and for that they need legendary tuning fork.  But the problem starts at the point when they found that they aren't the only ones who are looking for the fork.  And to make thing even worse it might not even be real.  then evil chef comes and kidnaps Cass's mother. Then they luckily found the fork but Cass's mother is still kidnapped and all they know is that she is is the zoo some where