French chef Thierry Drapeau has lost 20 years’ worth of recipes and has offered a €10,000 reward for its safe return. The chef was giving a series of masterclasses in Yekaterinburg, located in Russia’s Urals region, when his prized recipe-book went missing.

Russian chef Mikhail Kovalev is the restaurant director who was hosting Drapeau in the Russian city and has vowed to reunite the book with its rightful owner.

Thierry Drapeau runs his self-titled restaurant at Saint Sulpice le Verdon in the West of France. The classic dining establishment currently holds two Michelin stars.