In a large bowl, mix ricotta, 1 cup mozzarella, the egg, spinach, salt, oregano and pepper. In greased 13 x 9 x 2-inch baking dish, layer 1/2 cup sauce, third of noodles and half the cheese mixture. Repeat. Top with remaining 1/2 cup mozzarella. Pour water around edges. Cover tightly with foil. Bake in 350° oven 15 minutes, or until bubbly. Let stand 15 minutes before serving. Makes 8 servings. (This recipe eliminates one step. No need to cook noodles ahead.)