Pace flour eggs, water, tomato paste and oil in a food processer and process to combine. Turn dough onto a lightly floured surface and knead for 5 minutes or until dough is smooth and elastic. Wrap dough in plastic food wrap and set aside to stand for 15 minutes
To make filling place spinach, ricotta chesse egg parmesan cheese, nutmeg and black pepper to taste in a bowl and mix to combine
Divide dough in half and roll out one half to from a rectangle 30 *45 cm * 18 in. Spread with half the filling mixture leaving a 2.5 cm in border then top with half the prosciutto or ham then top with half the prosciutto or ham and half the mozzarella cheese. Fold in border on long sides then roll up from the short side. Wrap roll in a piece of washed calico cloth and secure ends with string. Repeat with remaining ingredient to make a second roll.
Half fill baking dish with the water and place on the top. Bring to the boil add roll reduce heat cover dish with the aluminium foil or lid and simmer for 30 minutes. Turn rolls once or twice during cooing . remove rolls from water and allow to cool for 5 minutes. Remove calico from rolls and refrigerate until firm.
Serve rolls into slices.