Peel and mince the garlic.
In a small bowl, combine the garlic salt, sugar, white pepper, cornstarch and cooking wine. Mix to thoroughly combine.
In a small bowl, combine the light soy sauce, dark soy sauce, rice vinegar, sugar, and chili sauce, if using.
Place the cod fillets on a sheet of paper towel and pat the fish dry.
Add oil to the marinaded cod. This helps remove some of the fishiness.
Boil 4 cups of water in a large pot over high heat. Add the remaining 1 teaspoon of the oil and salt. When water comes to a boil, add broccoli and lower the heat to medium. Simmer for 5 to 6 minutes and remove the broccoli.
Plate the cooked cod with the broccoli. Drizzle with finishing oil.
