Spinach and Mushroom Chicken Casserole

This idea morphed several times so no specific recipe was followed.

Chicken thighs, cubed and fried
Spinach and mushrooms, chopped and cooked down
Zucchini, chopped
Red onion, garlic, thyme, pepper, salt, vinegar (spicy)
Cream of mushroom soup
Parmesan cheese, grated

Cooked on stove top, finished in cast iron skillet at 375F