Place all ingredients and tools nearby. Begin by heating a splash of olive oil in a heavy-bottomed pot over medium heat.
Add diced onion, chopped carrots, and celery to the pot. Sauté, stirring occasionally, until the vegetables soften and release a sweet aroma, about 8 minutes. They should become slightly translucent and fragrant.
Add minced garlic to the vegetables and cook for another minute, until fragrant. You’ll hear a gentle sizzling and notice the garlic turning golden.
Nestle the bone-in chicken thighs into the pot, browning each side for about 5 minutes. Look for a golden-brown crust forming and a rich aroma filling the air.
Pour in the chicken broth, ensuring the chicken is mostly covered. Sprinkle in red pepper flakes and gently stir to combine. Bring the mixture to a gentle simmer.
Reduce the heat to low, cover the pot, and let it simmer quietly for 45 minutes to an hour. During this time, the chicken will become tender and start to fall apart, and the flavors will deepen.
Carefully remove the chicken thighs from the pot, placing them on a cutting board. Use two forks or a meat shredder to pull the meat apart into bite-sized pieces, discarding the bones.
Return the shredded chicken to the pot, stirring to combine. Taste the broth and season with salt and pepper as needed. Let the soup rest for about 10 minutes to allow the flavors to meld.
Serve the soup hot, ladling into bowls and garnishing with fresh herbs or a squeeze of lemon if desired. The broth should be rich, the vegetables tender, and the chicken succulent — a comforting, rustic dish ready to warm you from the inside out.
