First, make the sauce. Mix together in a small bowl: worcestershire sauce, oyster sauce, ketchup, soy sauce, and mirin. Set aside.
Then prepare the noodles. Add some cooking oil to a large pan over medium heat. Then place the noodles (which are typically sold in square packages) on the pan. Wait a few minutes for the noodles to warm through. Then flip the noodles and use chopsticks to gently (very gently!) loosen the noodles.Note: The purpose of the step is to loosen all the noodles without breaking them. Once all the noodles are loose, remove them to a plate and set aside. Before we go to the next step, make sure the meat and vegetables are prepared for cooking. The pork should be thinly sliced (you can purchase thinly sliced meats at most Asian markets) and then cut into bite-sized pieces.The onions and cabbage should be sliced. The carrots, julienned. Fresh shiitake mushrooms should be gently cleaned and sliced. And the beansprouts should be washed and drained. Now we cook the meat and vegetables! In the same big pan, add a little more cooking oil and turn the heat up to medium-high. Add the thinly sliced pork loin (or pork belly) and pan fry till just cooked through. This should only take a few minutes. Remove the pork to a separate plate and set aside.
Then add the onions to the pan. Stir-fry for about 3 minutes, until the onions start to brown.
Add the carrots and stir-fry for 3 more minutes.
Then add the cabbage and stir-fry for 3 minutes.
Followed by the shiitake mushrooms. Stir-fry for 3 more minutes.
Add the bean sprouts and stir-fry for 3 minutes.
Then add the pork loin or belly (already cooked) back to the pan.
Followed by the loosened noodles.
Pour the sauce (prepared in Step 1) on top.
Give everything a good mix. Cook for 1-2 more minutes, making sure that all the ingredients are well combined. The yakisoba dish is ready to eat! Enjoy hot ^_^