Season the chicken thighs and drumsticks with salt, pepper, and dried oregano.
In a large, heavy skillet over medium-high heat, heat the olive oil. Add the seasoned chicken pieces skin-side down and sear for about 5-7 minutes until golden brown. Flip and cook for another 5-7 minutes. Remove from the skillet and set aside.
In the same skillet, add the sliced onion, red bell pepper, and green bell pepper. Sauté for about 5 minutes until softened. Add the minced garlic and red pepper flakes, and cook for an additional 1-2 minutes until fragrant.
Pour in the chicken broth and lemon juice, scraping the bottom of the pan to lift any browned bits.
Return the seared chicken to the skillet, nestling it into the vegetables and liquid. Bring the mixture to a gentle simmer, then cover and let cook for 30-35 minutes, or until the chicken is cooked through and reaches an internal temperature of 165°F (75°C).
Once done, taste the sauce and adjust seasoning with salt and pepper if needed. Garnish with chopped parsley before serving.
Notes
Adjust the red pepper flakes for desired spice level.