This is the 5602nd most frequent Japanese word.
こだわる
To be particular about, to dwell on, or to obsess over details.
In this sentence, "こだわる" is used to express being meticulous or particular about certain aspects, here about the ingredients in cooking.
彼は素材にこだわって調理します。
He is particular about the ingredients he uses for cooking.
Here, "こだわる" means concentrating or being overly concerned with something, in this instance, minute details.
細かい点にこだわるべきではない。
You shouldn't focus excessively on minor details.
In this usage, "こだわる" conveys maintaining attention or adherence to one's personal style, signifying a form of attachment or pride.