Pulse together the flour and salt in a food processor. Add the lard or olive oil and pulse until well incorporated. Add the water, bit by bit, processing steadily, until a ball of dough forms. Transfer the dough ball to a board and knead lightly for a moment. The dough should be soft and quite pliable. If it's sticky, incorporate a bit more flour. Dust the dough with  flour, then wrap in a towel or plastic wrap and set aside for at least a half hour.

If your greens aren't sold pre-washed, rinse them well, in several changes of water if necessary. Parboil the greens in salted water just until wilted. Drain under cold water until they have cooled off. Then squeeze them dry and chop them roughly.

Make a soffritto by sautéing the pancetta, onion and garlic in some olive oil. Add the chopped greens and mix well. Let the greens absorb the flavors of the soffritto for a few minutes over moderate heat, seasoning generously as you go. Let cool completely, then mix in the parsley and grated cheese.

Divide the dough in two. Roll out one half into a thin round, then lay it over a well-greased baking pan about 27cm/11 inches in diameter. Lay the filling out all over the bottom of the pan. Roll out the other half of the dough and lay it over the filling. Trim off the excess dough and crimp the edges.

Prick the top layer of dough all over with a fork or a skewer. (This step prevents the top crust from puffing up.) Then brush the dough with olive oil. Bake in a hot (200C/400F) oven for a good 30 minutes, until lightly browned on top.

Let your erbazzone cool until just slightly warm. Cut into slices and serve. It is also quite nice at room temperature.