To make the ravioli filling: mix the fresh ricotta cheese with a little of the lemon zest, little of freshly grated nutmeg, salt and paper and little bit of pecorino and a couple of fresh mint leaves.
To make the ravioli: Place the pasta sheet at room temperature on the table, with you hands make little bowl with the ricotta mix, place it on the pasta and create a little hole with your thumb, it will contain the fresh egg yolk which has to be cracked one spot. Very carefully place a layer of pasta on the top of the egg and ricotta mix and with your finger make the raviolo, spread some egg wash on the edges. Cook the ravioli in boiling water for couple of minute - the egg has to be runny. At the same time make the sauce in a pan; use some chicken stock, butter, salt, pepper, some mint leaves at last minute and grated pecorino on top.