01 - Pat chicken breasts dry and season both sides generously with salt, black pepper, and paprika.
02 - Heat olive oil in a large skillet over medium-high heat. Sear chicken for 3–4 minutes per side until golden brown. Remove from skillet and set aside on a plate.
03 - Reduce heat to medium. Add butter to the same skillet. Sauté onion and mushrooms (if using) for 3–4 minutes until softened. Add garlic and cook for 30 seconds until fragrant.
04 - Sprinkle flour into the skillet and stir constantly for 1 minute to cook out the raw flour taste.
05 - Gradually whisk in chicken broth, milk, and heavy cream until smooth. Add thyme, parsley, salt, and pepper. Simmer for 2–3 minutes, stirring frequently, until slightly thickened. Stir in Parmesan until melted.
06 - Return chicken to the skillet, nestling into the sauce. Cover and reduce heat to low. Cook for 15–20 minutes until chicken reaches internal temperature of 165°F.
07 - Rinse rice under cold water until clear. In a medium saucepan, bring water or broth and salt to a boil. Add rice, cover, reduce heat to low, and simmer for 15–18 minutes until tender. Remove from heat and let stand covered for 5 minutes. Fluff with a fork.
08 - Place a bed of fluffy rice on each plate. Top with chicken breast and spoon generous amounts of creamy sauce over both.