Bring a large pan of salted water to the boil. While the water boils, heat a frying pan and sizzle the pancetta for 8 mins until crisp, then throw the broad beans into the pan with the pancetta fat. In a small bowl, beat the egg yolks with the cream and mustard, then season with lots of black pepper.
Cook the pasta following pack instructions. Drain the pasta, saving some of the water, and toss through the pancetta in the frying pan. Tip in the egg and cream mix, and stir to coat, adding a splash of the reserved water, if needed. Toss half of the grated Parmesan through, so the sauce clings to the pasta, then scatter with the remaining Parmesan.