Gourmet investigation: Who stole the recipe for Teurgoule?

Top chef Marie Ollait has just had the recipe for her fabulous Teurgoule, the famous Norman rice pudding, stolen. She's asking for your help!
The chef is sure that the culprit is a jealous restaurateur from the town! The teams play an initial game to find the names of the suspects. Then, in teams, the pupils set off along the streets to find the clues. They will then have to cross-reference the information to identify the culprit. Clues, evidence, suspects, motives... All the ingredients for a real detective adventure!