Shokugeki no Souma: San no Sara - Tootsuki Ressha-hen

A dark age of cooking befalls Tootsuki Culinary Academy. With the Elite Ten's devastating coup d'état, Azami Nakiri is now the director of the prestigious school. Students must now conform to Azami's ideology of "true gourmet food" and are forbidden to express creativity, or else face expulsion.

However, Souma Yukihira and the members of the Polar Star Dormitory refuse to accept these changes. Aided by other rebellious first-years, including the tenth seat, Erina Nakiri, Souma and his allies band together to fight off supporters of Azami's regime. But corrupt instructors and the menacing Central organization stand in their way, and so they must work together, harder than ever before, to survive every underhanded plot designed to banish them from the school.

(Source: MAL Rewrite)