Cook the farfalle in plenty of boiling salted water. In the meantime, wash drain and dry the swiss chards and slice lengthwise. Fry them for 2 minutes with a knob of butter in a nonstick pan. In a bowl, press the ricotta with a wooden spoon, add the Parmesan, the chards, a pinch of salt and pepper and 4 tbsp of the pasta’s cooking water and mix well. Drain the farfalle when al dente, dress with the prepared sauce and serve hot.