Marinate the cod chunks with salt, cooking wine, and a light dusting of flour. Let it sit for 5-10 minutes.
Bring a large pot of water to a boil. Once boiling, blanch the cod chunks until just cooked. Carefully remove them and set aside.
Heat oil in a pan over medium-high heat. Add the Doubanjiang, garlic, chopped spring onion whites, and chili powder. Sauté until fragrant and well combined.
Add a splash of water to the pan, stirring to create a saucy consistency. Adjust the amount of water to your desired sauce thickness.
Gently add the blanched cod chunks back into the pan. Season with soy sauce, oyster sauce,sugar, dashi powder (or MSG), and chili flakes. Stir gently to coat the fish evenly.
Garnish with chopped spring onion greens before serving. Enjoy it with steamed rice!