Prepare the broth:
Place the capon in a large pot with the vegetables and herbs.
Cover with water and bring slowly to a boil, removing the foam with a slotted spoon.
Cook over low heat for about 3 hours, then filter the broth and season with salt. Remove the capon from the pot and save it for other uses, such as a cold salad.
Prepare the dough:
Place the flour in a fountain shape on a pastry board and break the eggs in the center.
Knead the ingredients until you obtain a smooth and homogeneous dough. Wrap in cling film and let rest for 30 minutes.
Prepare the filling:
In a pan, cook the minced meat with a drizzle of oil and let it cool.
Blend together the cooked meat, mortadella, raw ham, Grana Padano, egg, a pinch of nutmeg, salt and pepper until you get a smooth mixture.
Shape the cappelletti:
Roll out the dough thinly with a rolling pin or pasta machine.
Cut out squares of about 4 cm side. Place a small amount of filling in the centre of each square, close it into a triangle and join the two corners to form cappelletti.
Cooking and serving:
Bring the broth to a boil, add the cappelletti and cook for 5-7 minutes (until they are soft).
Serve the cappelletti hot with the broth and sprinkle with Grana Padano DOP.