Heat a large pot or Dutch oven over medium-high heat. Add sesame oil and butter.

Once the butter has melted, add the scallions, garlic, ginger, and mushrooms. Sauté for 5 minutes, stirring, to not burn the garlic.

Add the miso paste, chicken broth, soy sauce, Sriracha, rice wine vinegar, brown sugar, and black pepper. Stir to combine. Bring the broth to a boil.

Once boiling, add the chicken thighs. Reduce heat to low and simmer for 15-20 minutes, or until the chicken is cooked through to an internal temperature of 165°F.

While the chicken cooks, make Instant Pot hard-boiled eggs (instructions below).

Remove the chicken and shred it with two forks. Set aside in a bowl.

Divide the noodles among 4 soup bowls. Ladle the broth over the noodles. Top each bowl with shredded chicken, egg halves, green onions, corn, chili crunch oil, lime wedges, and parsley.