Spaghetti with Chard and Parma Ham

I love Parma Ham - you get a salty savoury hit without too much meat, and it worked perfectly in tonight's quick pasta supper.  For 2 people, fry 2 or 3 slices of sliced Parma Ham in a little olive oil until crisp.  Remove to one side.  Wash a small head of Swiss Chard and cut across the head into thin slices.  Don't cut all the way down the thick stems for this dish.  Boil your spaghetti until al dente.  Whilst this is happening, saute a thinly sliced small onion for about 8 minutes until golden and soft.  Add a couple of cloves of crushed garlic, the prepared chard and a chopped ripe tomato to the onions and continue to saute, adding a little more oil, until the greens have wilted and the garlic is fragrant.  The tomato will start to break up to make a sauce.  Keep the heat brisk under the pan.  Season with black pepper and add the ham - you won't need any salt because this adds sufficient saltiness to the dish.  Drain the pasta, holding back a cup of the cooking water, and add to the chard mixture over the heat.  Toss together well, adding a little cooking water if dry.  Dish up and serve with plenty of grated Parmesan cheese.