Step 1

Put 20oz frozen oyster meat in a large bowl, submerge them in cold water for 10 minutes. Gently wash the defrosted oyster meat with cold water for 2 to 3 times, try not to break them.

Step 2

Drain the oysters, place them in a large pot, add 500ml cold water to the pot.

Step 3

Bring the water to a simmer over medium-high heat. Reduce the heat to medium-low, and keep the water simmering for 30 minutes. Meanwhile, use a ladle or a fine mesh skimming utensil to skim off the scum and foam from the broth.

Step 4

30 minutes later, the broth should have reduced by half. Transfer the oysters to a food container. You can use them to make oyster omelette later.

Step 5

Strain the broth through a fine-mesh sieve or cheesecloth-lined strainer (I used a pour over coffee dripper) into a cup. You should get about 250ml oyster broth if you don't spill any.

Step 6

Add cornstarch, sugar, salt, dark soy sauce, and water to a small bowl. Stir until well combined.

Step 7

Pour the oyster broth to a small nonstick pot, bring the broth to a simmer over medium-high heat. Reduce the heat to medium-low, pour the soy sauce cornstarch mixture to the pot. Stir continuously using a silicone spatula for 8 to 10 minutes, until the oyster sauce has been thickened into a caramel sauce texture.

Step 8

Transfer the oyster sauce to a sanitized food container, seal and store in the refrigerator for up to 1 month. (Always use a clean spoon to scoop the oyster sauce. No double dipper!)