Take the chicken off the bones and place the bones in a big soup pot.
Add about 4 quarts of water to the pot. You can add vegetables like onions and garlic to the broth.
Cover and boil for about 4 hours. The broth will evaporate and it should reduce down about halfway.
After it is reduced, strain bones out and place the clear broth back in the pot.
Rinse and pat dry chicken thighs. Heavily season the thighs with salt, fresh pepper, and garlic powder. Place in a frying pan with vegetable oil and cook until brown and crispy. Slice cook chicken into wedges.
Quickly boil the bean sprouts in a separate pot of water. Strain and add them to the main stockpot of broth.
Add sliced crimini mushrooms, enoki mushrooms, and sliced snap peas. Simmer broth.
In a large pot add water and bring to a boil. Add your udon noodles and cook according to the packages directions. I usually boil them for a couple of minutes until they are warm.
Add 3 tablespoons of sugar, 2 tablespoons of soy sauce and 1/2 tablespoon of salt. If your chicken was salted, don't add the salt portion. Btw, Costco chicken is brined with salt so we don't use extra salt.
If the flavor is weak, add the same ingredients in the last step. I usually double the seasonings, but I don't want to steer you to overly season it. It all depends on the broth and the chicken in regards to seasonings.
Add noodles and let simmer for about 10 minutes before serving. It is nice to allow the noodles to soak up the juices and seasonings.
Serve in a big soup bowl and top with sliced cooked chicken, fresh chopped green onions, squares of seaweed, furikake and freshly ground pepper.