Calorie's Love Affair

Calorie no Tsuyagoto is centered on Fuzuki Katori, a heavy-set woman who loves to eat and is sometimes ridiculed as "Calorie" by those around her. Although she is not uninterested in men, Fuzuki is shy and inexperienced in love because of her body type. However, her everyday life begins to change little by little after she meets a young university student, Shuugo Aoi, at a teishoku-ya (set meal restaurant) she happens to visit.

source: https://www.mangaupdates.com/series/nthdqui/karori-no-tsuyagoto