Sauté the onion until translucent, add the garlic and sauté until golden, add the tomato sauce, salt, oregano and dried parsley to taste, mix for 1 minute and set aside.
Unroll the pastry dough and fill it with the slices of mozzarella and ham, cut off the dough around to the filling, spread the soft cheese or creamy cheese over the filling and spread it out well, add another slice of cheese and roll it up tightly to seal properly, repeat this process until you've used up all the filling.
Add half of the sauce into a baking dish, spread evenly, place all the cannellonis over the sauce, cover them with the rest of the sauce and sprinkle some parmesan cheese all over it.
Cover with aluminum foil and bake in a preheated oven at 180°C (356°F) for 25 minutes. Remove the foil and bake for another 5 minutes, to brown.