In a large bowl, combine the ground chicken, cooked rice, egg, onion, salt, pepper, paprika, mustard powder, and dried parsley. I like to use my hands to mix all ingredients well.
Scoop out about two tablespoons of meat mixture and roll them into balls. The meat mixture is very soft, so wet your hands to make it easier to form the balls. Roll the balls in flour and make sure to dust off any excess.
In a large skillet, heat the olive oil over medium-high heat and brown the meatballs for about four minutes on each side and until fully cooked. I like to use two forks to flip them. Don’t worry if they are not perfectly round after this. Transfer to a plate.
Using the same skillet, melt the butter and add the flour. Cook the flour until just barely golden and whisk in the chicken broth.
Once it starts to thicken, add the heavy cream, red pepper flakes, fresh parsley, salt, and pepper to taste. Bring to a simmer and cook until it coats the back of a spoon.
Return the meatballs to the skillet and cook for about three minutes turning them into the sauce to coat them on all sides.