Heat olive oil in a large deep skillet or Dutch oven over medium-high heat.
Season the chicken thighs with salt and black pepper on both sides.
Place the chicken thighs skin-side down in the skillet and sear for 5-6 minutes until the skin is golden brown and crisp. Flip and cook for an additional 3 minutes. Remove the chicken from the skillet and set aside.
Reduce heat to medium. Add the chopped onion to the skillet and sauté for 3-4 minutes until translucent.
Add the minced garlic and cook for 30 seconds until fragrant.
Add the rinsed rice to the skillet and stir to coat the rice with the oil and onion mixture.
Pour in the chicken broth, lemon zest, lemon juice, and dried oregano. Stir to combine.
Return the chicken thighs to the skillet, placing them on top of the rice, skin-side up.
Bring the mixture to a gentle simmer, then cover the skillet with a tight-fitting lid.
Reduce heat to low and cook for 25 minutes, or until the rice is tender and the chicken is cooked through (internal temperature of 165°F/74°C).
Remove the skillet from heat and let it rest, covered, for 5 minutes.
Fluff the rice with a fork, garnish with chopped fresh parsley, and serve hot.