Put cooked rice into a 9 X 13 greased pan.
Mix next 7 ingredients and cook until thickened.
Pour over rice
Put cooked chicken on top of sauce.
Melt Velveeta a little and stir in sour cream and put on top of chicken.
Top with crushed Ritz crackers that are mixed with the melted butter.
Bake at 350 until heated through, about 30 mins.