Spray a 1 ½-quart casserole dish with cooking spray and set aside.
In a large bowl, stir together all of the ingredients. Transfer to prepared dish.
Bake casserole, uncovered, for approximately 30 minutes (or until heated through).
If you want to add some cheese, just sprinkle the grated Cheddar over the top of the casserole during the final 5 minutes of baking. Return to oven until cheese melts and casserole is hot and bubbly.
Notes
Nutrition information was calculated using Campbell’s Healthy Request Cream of Mushroom Soup and whole milk. The optional cheese is not included in the calculation.