Need serious advice with letter of recommendation authenticity.... :/

Hey guys, I've had a Chinese instructor for many many years (my parents believe its important to be bilingual! lol -.-). At first I met my instructor through a Saturday school type thing where she was teaching 20 other kids. After a while, she left the school and started giving private lessons because she made more this way. Since then, I've been privately instructed by her for like ~7 years ish (stopped when I went to university).

I want my LOR to be from her because she knows me so well and...

Need serious advice with letter of recommendation authenticity.... :/