In a large pot, place the bone-in skin-on chicken thighs and cover with water. Add the crushed garlic, halved Thai chili peppers, lightly crushed ginger, quartered shallot, and kosher salt. Bring to a vigorous boil over medium-high heat, skimming off any foam that rises to the surface. Once boiling, reduce the heat to low and let it simmer gently for 45 to 60 minutes, until the chicken is cooked through and tender.

After simmering, carefully remove the chicken thighs from the pot and allow them to cool slightly. Once cool enough to handle, shred the chicken from the bones, discarding the skin and bones. Set the shredded chicken aside on a plate.

Using the same soup pot, heat a couple of tablespoons of neutral oil over medium heat. Once hot, add minced garlic, quartered shallot, and lightly crushed ginger. Sauté for about 1 minute until the mixture becomes aromatic and the shallot is translucent.

Stir in the cubed sweet potatoes into the pot with the sautéed aromatics. Season with a pinch of salt and continue to sauté for an additional 3-4 minutes.

Pour the prepared broth back into the pot, along with the shredded chicken. Bring the mixture to a rolling boil, then reduce the heat to low and let it simmer uncovered for 30 to 35 minutes.

Once the sweet potatoes are tender, stir in the sesame oil for added depth and the green parts of the minced scallions. Let the soup rest for about 5 minutes off the heat.

Ladle the soup into bowls, garnishing each with the reserved scallion greens and a sprinkle of furikake or sesame seeds if desired.