Prepare the toppings (sliced Yakibuta, boiled eggs, green onions, and cooked corn), before making the soup and noodles. Once the noodles are cooked, you will need to add the soup and toppings right away or the noodles will get soft, so you won't have time to prepare the toppings at the end.
Put Ingredients A in a large pot and let boil for 15 minutes. Try to remove the fat while cooking. Strain, then put the broth back in the pot.
Add ingredients B to the broth and let it simmer at low heat.
While cooking pasta, add ingredients C to the soup and stir.