Spinach Stuffed Shells

This recipe makes a LOT - almost 2 full 9x13 pans. Half the recipe should still fill a 9x13 pan.

12 oz. jumbo pasta shells 
32 oz. spaghetti sauce (Prego traditional is a good choice)

Two 9 oz. boxes frozen creamed spinach

15 oz. ricotta cheese
1 pint sour cream
8 oz. shredded mozzarella cheese, divided
1 tsp. salt
1/4 tsp. pepper

Cook shells according to package directions. Spread a layer of sauce on bottom of pan. Cook the spinach and drain. Mix the rest of the ingredients together (minus sauce and 1/2 of mozzarella) then add cooked spinach to the mixture. Stuff the shells. Pour the rest of the sauce over the shells in the pan. Sprinkle top with remaining mozzarella. Bake at 350º for 30 minutes.