Add tomatoes, tomato paste, and ½ cup water mashing tomatoes with wooden spoon. Bring to boiling; reduce heat; simmer, covered and stirring occasionally, until thick 1 ½ hours. In a kettle bring 3 quarts of water and l tablespoon salt to boiling. Add lasagna, 2 or 3 at a time. Return to boiling, boil uncovered and stirring occasionally about 10 minutes. Drain in colander. Preheat oven to 3750. In a medium bowl, combine ricotta, egg, remaining parsley, and salt; mix well. In bottom of 13 x 9 x 2 inch baking dish, spoon 1 ½ cups sauce. Layer with 6 lasagna, lengthwise and overlapping, to cover. Spread with half of the ricotta mixture, top with third of mozzarella. Spoon I ½ sauce over cheese; sprinkle with ¼ Parmesan. Repeat layering, starting with 6 lasagna and ending with 1 1/2 cups sauce sprinkled with parmesan. Spread with remaining sauce; top with rest of mozzarella and parmesan. Cover with foil, tucking around edge. Bake 25 minutes· remove foil· bake uncovered 25 minutes longer, or until bubbly. Cool 15 minutes before serving.