Clean and slice the fresh mushrooms and cut the cooked ham into small pieces. Prepare 2 large pots.
In a saucepan, sauté the finely chopped onion and the finely chopped garlic cloves in a little olive oil until translucent. In the meantime, add water to the second pot and cook the spaghetti al dente.
Cut the cans of tomatoes into small pieces with a knife and remove any peel remains and stems. Put the tomatoes and ham with Italian herbs in the saucepan. Salt is not necessary as the ham gives off enough of it.
Add the mushrooms to the sauce a little later, as they will stay crisp and not so watery. Pour the fresh parsley and a dash of cream into the sauce. Drain the spaghetti and serve with the sauce.