Season the chicken thighs on both sides with salt, black pepper, dried thyme, and dried oregano.
In a skillet over medium heat, add olive oil. Once hot, add diced onions and sauté for about 3-4 minutes until they become translucent. Add minced garlic and cook for an additional minute until fragrant.
In your slow cooker, place the seasoned chicken thighs at the bottom. Pour the sautéed onions and garlic over the chicken.
Sprinkle the uncooked rice over the chicken and onions, then pour in the chicken broth. Add the lemon juice and lemon zest. Stir gently to combine, ensuring that the rice is evenly distributed but keeping the chicken on the bottom.
Cover the slow cooker and set it to low for 6-7 hours or high for 3-4 hours, until the chicken is tender and thoroughly cooked.
About 30 minutes before serving, add the frozen peas to the slow cooker, gently stirring them in.
If desired, shred the chicken thighs with two forks, then mix it back into the rice for a more homogenous dish.
Serve the chicken and rice hot, garnished with freshly chopped parsley for a burst of flavor and color.
Notes
For a more homogenous dish, shred the chicken and mix it back into the rice before serving.