Kougetsu An, a well-established Japanese-style confectionary store where Nao's mother worked and lived is where she met Tsubaki. However, after a certain incident, Nao's mother was accused of murder and is arrested. Because of that, Nao was banned from Kougetus An. Fifteen years later, Tsubaki revisits a disapproving Nao, which make the two compete at a showdown for their skills. The hateful Tsubaki who once made Nao's life a crazy mess approached Nao later to marry him since he has yet to notice that his long-lost childhood friend is Nao. How will Nao react to this unexpected proposal?!
-from mangaupdates-

七桜は幼いころ、母が住み込みで働いていた老舗和菓子屋・光月庵で椿と出会う。しかしある事件が起き、殺人の容疑をかけられた七桜の母は逮捕され、七桜も追い出されてしまう。15年がたち、失意の七桜の前に現れた椿。二人は和菓子の腕を競って対決することに。七桜の人生を狂わせた椿。その憎い椿は、あろうことか七桜に自分との結婚を持ちかける。七桜をかつて幼なじみとだは気づいていない椿。思いもよらない言葉に七桜は!?

Source: Michex Reading Lounge