Bring a large pot of salted water to the boil, add the penne, and cook according to the packet instructions.
Whisk the egg in a bowl with the sea salt, freshly ground black pepper, freshly grated parmesan and double cream.
Chop up your pancetta, put it in a frying pan with a splash of olive oil and cook until golden and crispy.
Take a peeler and slice long strips off skin of the zucchinis. Save the skins and throw out the cores. Then add the zucchini skins in with the pancetta at the last minute and give them a stir.
Drain the pasta but save some of the pasta water. Add the pasta to the pancetta and stir in most of the finely sliced mint.
Take the frying pan from the heat and wait for the sizzling sound to stop (30 seconds). Then add the egg and cream mix and stir it around. The heat of the pasta will cook the egg mix without scrambling it.
Toss together and loosen with a little of the reserved cooking water.
Season with salt and pepper, some fresh parmesan and a couple of mint leaves and serve.