Dice the red and yellow bell peppers and onion on a cutting board. Set them aside.
In a small bowl, combine the olive oil, paprika, garlic powder, salt, and pepper. Season chicken by rubbing this mixture evenly over the chicken breasts.
Preheat your cast iron skillet over medium-high heat. Add a drizzle of olive oil, vegetable oil or avocado oil and swirl to coat the large cast iron skillet. Carefully place the seasoned chicken breasts in the skillet. Sear on the stove top for 3-4 minutes per side, or until golden brown and fully cooked. Remove chicken and set aside.
In the sam pan, add the diced peppers and onions. Cook over medium heat until softened, about 5-10 minutes.
In a small saucepan, combine the rice, chicken broth, and tomato paste. Bring to a boil, then reduce heat to low, cover, and simmer for 15 minutes, or until the rice is cooked through and all the liquid is absorbed. You can also use premade rice, microwavable rice, instant rice or frozen rice. Just make sure the rice is cooked before adding it to the skillet.
Add the chicken back to the pan with the peppers and onions.
Once the rice is cooked, stir the rice into the pan with the chicken, sautéed peppers and onions.
Preheat your oven to 400°F (200°C). Top the rice mixture with grated Parmesan cheese and drizzle with a little olive oil. Transfer the skillet to the preheated oven and bake for 30 minutes, or until the chicken is cooked through and reaches an internal temperature of 165°F (74°C). I lke to use a meat thermometer to make sure! I also like to let my cooked chicken rest for a few minutes after removing it from the oven.
For best results garnish the Tuscan Cast Iron Chicken Breast with Rice with fresh parsley, lemon zest, black pepper and sea salt or kosher salt (optional) and serve immediately. Enjoy!