Spaghetti with Red Onions, Sun Dried Tomatoes, Balsamic Vinegar and Basil

1lb dried spaghetti, the best you can get
1 red onion, peeled and finely chopped
Olive oil
2 handfuls of sun-dried tomatoes in oil, chopped
3 tablespoons balsamic vinegar
Salt and freshly ground black pepper
2 handfuls of basil, torn
1small handful of Parmesan or pecorino cheese, grated

While cooking the Spaghetti in plenty of salted boiling water until al dente, slowly fry the onion in a couple of lugs of olive oil, for 5 minutes until soft and tender. Stir in the drained tomatoes and vinegar, and throw in your drained pasta. Season and serve.