The Great Cleric: Volume 1 (Light Novel)

A great and mature progression with in-world realism. Didn't feel like a typical teen power fantasy, which was quite refreshing. The main character isn't an omnipotent godlike creature who learns top level stuff in minutes, and it didn't frustrate with the standard Japanese tropes, like recreating soy sauce or their social rules and culture. One of the better isekai novels out there.