It is popular in Vietnamese and Chinese cooking. Fermented bean curd is very strong in flavor so a little bit goes a long way.
I sometimes mash up one cube of chao to eat with a bowl of rice porridge. More likely though, I mash it up and use it to flavor sauces or vegetables.
My recipes with chao/doufu ru (fermented bean curd):
Rau Muong Xao Toi Voi Chao (Vietnamese Water Spinach Sauteed with Garlic and Fermented Bean Curd)
Dau Hu Nhoi Cha Tom voi Sot Chao Ot (Vietnamese Shrimp Paste-Stuffed Tofu with Fermented Bean Curd Chili Sauce)
Yong Tau Foo (Chinese Stuffed Tofu)
1 year ago today, Egg Rolls Stuffed with Bananas and Mangoes with Nutella Dipping Sauce.