Meanwhile, in a small sauce pan over low heat, melt the butter. Slowly whisk in the flour until completely combined with no chunks (a thick dough will form). Stir over medium heat for 1 minute. Gradually add in the chicken stock or broth, whisking constantly. Add in the pepper, garlic powder, onion powder, salt, and Italian seasoning. Allow to thicken and then gradually add in the milk, whisking constantly.
Stir over low heat until thickened. Stir in the freshly grated (pre-grated tends to get greasy) cheddar cheese and mix until melted and smooth. Add in the sour cream and shredded chicken. Stir until chicken is warmed through.
Prepare your haystacks! Top each place with even amounts of rice and then even amounts of the cheesy creamy chicken!
Top the chicken with your favorite toppings: shredded coconut, olives, chunked pineapple chow mein noodles, a chopped red pepper, green onions, extra cheddar cheese, etc.!