Place all ingredients on your workspace: the chicken thighs, chopped carrots, celery, diced onion, minced garlic, chicken broth, red pepper flakes, and season with salt and pepper.
Heat your heavy-bottomed pot over medium heat and add a splash of olive oil. Once shimmering, add the diced onion, carrots, and celery.
Sauté the vegetables for about 8 minutes until they soften slightly and turn fragrant, with a light golden hue around the edges.
Add the minced garlic to the pot and cook for another minute until it becomes fragrant and slightly golden.
Nestle the bone-in chicken thighs into the vegetables, browning each side for about 5 minutes until golden and slightly crispy.
Pour in the chicken broth, add red pepper flakes, and stir gently to combine everything. Bring the mixture to a gentle simmer.
Reduce the heat to low, cover the pot, and let everything simmer for about 45 minutes to an hour, until the chicken is tender and falling apart.
Remove the chicken thighs from the pot and set aside to cool slightly. Use two forks or a meat shredder to pull the chicken into shredded pieces.
Return the shredded chicken to the pot, stirring to combine and letting it reheat in the flavorful broth.
Taste the soup and adjust the seasoning with more salt, pepper, or red pepper flakes if desired. Let it sit for 10 minutes to allow flavors to meld.
Serve the soup hot, garnished with additional herbs or a squeeze of lemon if you like a bright finish. Pair with crusty bread for a complete, comforting meal.
