2 oz grated parmesan cheese, or pecorino romano cheese (56gm)
Cook Spaghetti according to package directions, omitting salt and fat; drain.
While pasta cooks, heat 1 tablespoon oil in a large nonstick skillet over medium-high heat. Add scallops and shrimps to pan; cook 3 minutes. Remove scallop mixture from pan; keep warm. Heat remaining 1 tablespoon oil in pan over medium-high heat. Add onion, red and green capsicums, and garlic; cook 2 minutes. Add tomato paste and tomatoes; bring to a boil, and cook 2 minutes. Add a bit water; cook 1 minute. Add mussels; cover and cook 4 minutes or until mussels open. Discard any unopened shells. Stir in scallop mixture, parsley and parmesan chees; cook 1 minute or until cheese is melted. Serve over pasta.