Heat your skillet over medium-high heat and melt the butter. Add diced onion and sauté until it softens (approx. 2-3 mins).
Introduce the cubed chicken to the skillet and season with kosher salt, freshly ground black pepper, thyme, and rosemary. Cook until chicken develops a golden-brown crust on all sides, roughly 5 minutes. Stir in the minced garlic and cook for another minute.
Pour in chicken broth and rice, and mix until well combined. Bring the mixture to a boil, cover your skillet, and turn down the heat to medium-low.
Allow the mixture to simmer until the rice becomes tender (about 15-20 mins). Once ready, take off the heat and mix in the heavy cream and freshly grated parmesan.
Serve this scrumptious meal with extra parmesan and a sprinkle of chopped fresh parsley if desired.