Cut the onions and green onions into bite-sized pieces. Cut the cucumber (if using) into thin matchsticks. Cut the pork belly into thin strips.

In a non-stick wok (or pan), add the black bean paste and enough oil. The amount of oil should be about ½ of the black bean paste. Place it over medium heat and make sure to keep stirring it.

Once you can see some bubbles in the middle, turn the heat off and transfer it to an airtight container.

In another wok, add the cooking oil (3 tbsp). You can use the oil that you fried black bean paste with. Once it gets nice and hot, add the pork and render out the fat.

Once it becomes dark golden brown, add ginger (½ tsp) and soy sauce (1 tbsp). Be careful of oil splatter.

Add ½ of the green onions and stir-fry it until fragrant. Add the remaining green onions and stir-fry it over high heat.

Add the sugar, oyster sauce, chicken stock (or chicken bouillon powder), and fried black bean paste. Mix everything together.

Add water (200ml) and simmer it for more than 5 minutes.

Meanwhile, prepare the slurry. In a small bowl, mix together potato (or corn) starch and water. Add the slurry into the sauce and immediately stir it until the sauce gets thicker. Cover and keep warm until ready to serve.

Bring a pot of water to a boil. Cook the noodles according to the package instructions. (If you are using fresh noodles, rinse them under cold water and drain.)

Divide the noodles into serving bowls and add the sauce. Garnish with cucumber (if using). Serve with kimchi or Korean pickled radish. Enjoy~!