Add cream cheese, Parmesan and noodles ... or until mixture begins to thicken. Fold in chicken. Pour into a 3-quart casserole dish. Sprinkle on reserved topping mixture. Bake uncovered 15 minutes.
Season the chicken thighs all over with a little salt and lots of black pepper. Heat the oil in a large non-stick casserole pan over a medium heat and fry the chicken for 7–8 minutes ...
Any remaining mash can be set aside for another recipe. For the chicken casserole, trim the chicken thighs of any fatty bits and cut each one into four pieces. Season well with salt and pepper.
Add chicken and rice and return to a simmer. Stir in peas, parsley, and sour cream; season with salt and pepper. Transfer the mixture to an 8-inch square baking dish. Top with breadcrumbs.