What is Reddit's opinion of Phoenix Claws and Jade Trees: Essential Techniques of Authentic Chinese Cooking: A Cookbook?
From 3.5 billion Reddit comments

By popularity on Reddit, this product is:

#59 in Chinese Cooking, Food & Wine books

1 review of this product found across Reddit:

Hmm... so in general I think there's two main approaches for learning cooking: (1) trying your favorite dishes and throwing yourself into them or (2) finding something a bit more systematic that your can build your skills on. Personally, I like a combination.

For English language sources, unfortunately there's a lot out there that's pretty variable. Online, I'm biased but I do like to think we do a good job. There's also the blog China Sichuan Food which's also quite legit. And while it's in Chinese, the ever popular Wang Gang is always an awesome source... a handful of his vids even have (poorly translated, but still) English subs.

Regarding something a bit more systematic, unfortunately the English language is a bit more barren on that front. I think Kiam Lam Kho's Pheonix Claws and Jade Trees is probably the best out there.

Other decent sources with cookbooks are Grace Young and Fuschia Dunlop.