Preheat over to 350 degrees.
In large bowl combine the soup, milk, sour cream , Ro-Tel, about half of the cheese, taco seasoning and cooked chicken.
In a 9x13 layer casserole as follow; Refried Beans, 1/3 of Doritos, 1/2 Chicken Mixture, 1/3 of the Doritos, 1/2 of Chicken Mixture, Rest of Cheese, Rest of Doritos.
Cover with Aluminum Foil and bake for 30-35 minutes, uncover and bake for 5 more minutes.
Top with any toppings you want and serve.