Combine soup & lemon juice. Saute green pepper, and add to sauce. Break spaghetti into 1” pieces, and boil in salted water ½ the recommended time. Drain spaghetti. Mix spaghetti, chicken, & mushrooms into sauce.
To Freeze: Place mixture into oven & freezer safe baking pan. Sprinkle parmesan cheese over the top. Cover, label, and freeze.
To Serve: Thaw completely. Bake at 350 for 45-60 minutes, or until thoroughly heated.
*Frozen casserole may be baked for 1 ½ hours at 350.
Bake at 350 degrees for one hour, or until thickest piece is done. Remove from oven and cool.