Pre-heat oven to 350 degrees. Spray a 9x13 baking dish with non stick cooking spray.
In a small bowl combine cream of mushroom soup, sour cream, milk, thyme, garlic powder, black pepper, and salt.
Using the same pot you boiled the pasta in, combine chicken, pasta, spinach, mushrooms, and pimentos.
Add sauce mixture and combine well. Pour into baking dish. Cover evenly with cheddar cheese.
Bake for 30 minutes, until casserole bubbles and has turned golden brown.
To complete the meal, serve with a garden salad and garlic bread. *Tip to get “Kids in the Kitchen!”- Let them stir! This recipe has lots of opportunities to stir! That is the most fun part! Involve kids by allowing them to do everything from measuring the spices to pouring pimentos into the pot. Kids are more likely to eat a dish they helped prepare!