Preheat the oven to 350°F (175°C).
In a medium saucepan, bring 2 1/4 cups water to a boil. Stir in the Knorr Rice Sides – Chicken flavor. Cover, reduce heat to low, and simmer for 15 minutes or until rice is tender and water is absorbed. Remove from heat and fluff with a fork.
While the rice cooks, heat olive oil in a large skillet over medium heat. Add the chopped onion and cook for 3-4 minutes until softened.
Add the minced garlic to the skillet and cook for 1 minute until fragrant.
Add the bite-sized chicken pieces to the skillet. Season with salt, black pepper, and paprika. Cook, stirring occasionally, until the chicken is cooked through and no longer pink in the center, about 7-8 minutes.
In a large mixing bowl, combine the cooked rice, cooked chicken mixture, sour cream, milk, half of the shredded cheddar cheese, half of the shredded mozzarella cheese, and dried parsley flakes. Stir well to combine.
Transfer the mixture into a greased 9×13-inch casserole dish and spread evenly.
Sprinkle the remaining cheddar and mozzarella cheese evenly over the top of the casserole.
Bake uncovered in the preheated oven for 20 minutes, or until the cheese is melted and bubbly and the casserole is heated through.
Remove from the oven and let it rest for 5 minutes before serving.