Season the tomatoes, puree, pass through a sieve, retain the juice.
Heat the oil in a frying pan, reduce the heat, gradually add the spinach, sauté for approx. 5 mins. Squeeze out the resulting liquid, allow the spinach to cool slightly, chop finely.
Mix the ricotta with all the other ingredients up to and including the egg, season. Stir in the spinach.
Using 2 teaspoons, shape the mixture into oval-shaped dumplings. Cook the gnudi in boiling, salted water for approx. 10 mins. per batch. Remove with a slotted spoon, drain. Serve the tomato salsa with the gnudi.