Trim the courgettes, rinse well and dice them. Blanch the tomatoes for a minute, then, once drained, deseeded and peeled, dice the pulp. Finely slice the garlic and the onion and toss them in a pan with a dash of warm oil then fry until soft over a medium heat.Add the courgettes, a pinch of salt and a grind of pepper and brown for 7-8 minutes, mixing with a wooden spoon. In the meanwhile cook the pasta in plenty of boiling water; drain it al dente, then mix it with the vegetable sauce.Toss everything in the same pan, add the diced tomatoes and sauté over a medium heat. Serve immediately. A variation: you may add a touch of Mediterranean fragrance to the sauce with a couple of basil leaves, then sprinkle some chopped basil too, once the penne are dressed.