zucchini casserole

This is soo good!  Everytime I make it people ask for the recipe.

6 C. Sliced Zucchini
1 Can crm chicken soup
1 1/2 C. Shredded Cheddar Cheese
1/2 C. butter
1 C. Sour Cream
8 oz. Stove Top
1 C. Carrots, grated
1 Medium Onion
1 C. Mushrooms (optional)

Saute Onions, but don't brown.  Mix onions, sour cream, carrots, soup, and cheese.  Melt butter and mix with stove top. 

Layer Pan: Stuffing, mixture, zuke's, stuffing.  Bake @350 for 45-60 min.