Heat a large skillet over medium heat and add the olive oil. Swirl to coat the bottom.

Season the chicken breasts on both sides with salt and pepper.

Add the chicken to the skillet and cook until browned and cooked through, about 6 to 7 minutes per side. An instant-read thermometer should read 165°F (74°C). Remove the chicken and set aside to rest.

In the same skillet, add the chopped onion and minced garlic. Sauté until the onion is softened and translucent, about 3 to 4 minutes, scraping up any browned bits.

Stir in the rice and cook for 1 to 2 minutes until the grains are lightly toasted.

Pour in the chicken broth and heavy cream, then stir to combine and bring the mixture to a simmer.

Bring the mixture to a boil, then reduce the heat to low, cover the skillet, and simmer gently for 15 to 20 minutes, or until the rice is tender and most liquid is absorbed.

Return the cooked chicken to the skillet, add the frozen peas if using, and heat through for 2 to 3 minutes.

Taste and adjust seasoning with salt and pepper. Garnish with chopped parsley before serving.