Spread 1/3 of the spaghetti sauce in ungreased 13 x 9 x 2" baking pan. Mix spinach, cottage cheese, Parmesan cheese, oregano and pepper in a mixing bowl. Fill uncooked manicotti shells with spinach mixture; arrange on spaghetti sauce in dish. Pour remaining spaghetti sauce evenly over shells, covering completely. Sprinkle with mozzarella cheese. Cover and bake in 350 degree oven until shells are tender, about 1-1/2 hours. NOTE: If making Baked Stuffed Pasta Shells, you will need to cook the pasta noodles in boiling water, according to package directions. Cool before stuffing. Proceed as above. Posted to rec.food.recipes by ag261@cleveland.freenet.edu (Ray Taylor) on Sep 30, 1994.