What to gift to your Female Japanese teacher?

Hi. I need a little help. My girlfriend is going to visit her past 日本語学校 homeroom teacher after more than a year tomorrow and we are looking to give her sth. as a present but we are so lost here. She is a 50 ish year old woman who was very caring of my girlfriend. Thank you.

Ps: I’m going to the Aeon Mall nearby. If there is anything i should buy please let me know.

by omoiavas1