In a large pot, bring the chicken broth to a boil. Add the chicken thighs or drumsticks and cook until tender, about 20-30 minutes.
Remove the chicken from the broth, let it cool, and then shred or chop into bite-sized pieces. Set aside.
In a separate pan, heat the vegetable oil over medium heat. Add the minced garlic and chopped onion, and sauté until softened and fragrant.
Add the ground turmeric, coriander, cumin, and black pepper. Cook for another minute, stirring constantly.
Add the sautéed spice mixture to the chicken broth. Stir well to combine.
Add the smashed lemongrass, kaffir lime leaves, and galangal slices. Simmer for 10 minutes to infuse the flavors.
Return the shredded chicken to the pot. Season with fish sauce, soy sauce, and salt to taste. Simmer for an additional 5 minutes.
Blanch the bean sprouts in boiling water for about 1 minute, then drain and set aside.
Prepare the hard-boiled eggs, shredded cabbage, green onions, and cilantro.
Ladle the hot soup into bowls. Top with bean sprouts, hard-boiled eggs, shredded cabbage, green onions, and fresh cilantro.
Enjoy your meal!