Cut the meat into 1 in / 2.5 cm.dice, and brown lightly in the grapeseed oil, cooking it for 8–10 minutes. Drain the meat, and put it on a chopping board. Chop the meat finely, then mix in the egg, salt, nutmeg, Parmesan and finally the breadcrumbs. Mix by hand, and knead and work it for 5 minutes until the mixture is too soft.
Put the filling in a bowl, cover and keep until required. Use the same day.
Pile the flour on to a work surface, make a well in the centre, and slide in the eggs. Working with your fingertips, gradually draw the flour from the edge to the centre, and blend with the egg by hand until a dough is formed. Sprinkle with more flour if the mixture is sticky, which it may well be if you are working in a humid atmosphere. Knead for 5–10 minutes until the dough is smooth and elastic. Cover and let it rest for 15 minutes at room temperature.
Roll out the pasta on a floured working surface to a thickness of approximately ⅛ in / 0.2cm, stretching and rolling the dough over the rolling pin. (A long narrow pin, or matarella, is used in Italy.) It is easier to roll out smaller pieces of dough unless you are very practised at it. With a fluted cutting wheel, cut out squares of dough. Place a small, pea-sized ball of filling in the centre of each square of dough. Fold one corner over to the opposite and pinch the two edges of the triangle together very hard to seal them. Bend the central point of the triangle up and draw the other two points together around your finger. Pinch together to seal. Put the completed tortellini on a damp cloth until you have made them all.