In a large skillet, heat the olive oil over medium heat. Add the minced garlic and sauté until fragrant, about 1 minute. Be careful not to burn it; we want that lovely garlic flavor without bitterness.
Next, add the chicken pieces to the skillet. Season with salt, pepper, and red pepper flakes if using. Cook until the chicken is lightly browned and cooked through, about 5-7 minutes. Once done, remove from heat and set aside.
In the same skillet, pour in the chicken broth and bring to a simmer. Stir in the heavy cream, lemon juice, thyme or rosemary, and 1/2 cup of the Parmesan cheese. Mix well until the cheese is melted and the sauce is creamy.
In a large mixing bowl, combine the uncooked rice, broccoli florets, and the cooked chicken. Pour the creamy sauce over the mixture and stir until everything is well coated.
Preheat your oven to 350°F (175°C). Transfer the mixture into a greased casserole dish, spreading it evenly. Top with the remaining 1/2 cup of Parmesan cheese and breadcrumbs for that delightful crispy topping.
Cover the dish with foil and bake in the preheated oven for 30 minutes. Remove the foil and bake for an additional 10-15 minutes, or until the top is golden and bubbly. Your kitchen will smell divine!