For filling, in a large mixing bowl combine spinach, tuna, Ricotta cheese, Parmesan cheese ... on both long sides of rectangle just to edge ... or 8 appetizer servings.
Heat oven to 375 degrees. Beat egg slightly. Stir tuna, onion, cheese, parsley, celery ... beginning at long side with sealed edge down, shape ... in cheese until melted.
Heat oven to 425 degrees. ... minute. Stir in tuna, peas and lemon juice. ... beginning at wide side. Seal well by pinching ... 20-25 minutes. 4-6 servings.
Heat oven to 375 degrees. ... the egg. Stir tuna, onion, cheese, parsley, celery ... beginning at long side. With sealed edge down, ... 4 to 6 servings.
Heat oven to 375 degrees. ... remaining egg, the tuna, onion, cheese, parsley, celery ... beginning at wide side. Place seam side down ... 1/2 can of water.