Add the grano cotto to a saucepan, along with the other indicated ingredients, over low heat. Bring to a simmer and cook, stirring frequently, until the mixture turns creamy and porridge-like, usually about 5-10 minutes. Turn off the heat and let the mixture cool completely.

Pour the ricotta into a large mixing bowl. Add the sugar and whisk vigorously until the sugar is well incorporated and the mixture is rather fluffy. Mix in the eggs as well, one by one. Now add the cooled grano cotto, folding it into the ricotta cream until well incorporated. Add the cinnamon, vanilla and a few drops of orange blossom water. Taste and adjust the seasoning. Add more orange blossom water if you want a more perfumed filling, taking note that its intensity will lessen in baking. If you have the time, let this mixture rest in the fridge overnight. If not, even a few hours will do it good.

Mix the flour and sugar together by pulsing in a food processor. Then add the lard or butter and pulse until you have a sand like texture. Then add the egg yolks and mix again until the dough forms a ball, adding a bit of water, spoonful by spoonful, if need be. Cover the dough ball with plastic wrap and place in the fridge to chill for at least 30 minutes or until needed.

Take the dough out of the fridge. Take about 2/3 of the dough and roll it out into a round. To do this, I like to form the dough into a ball, flour it to avoid sticking, then beat it out flat with a rolling pin first, turning it around, then over, to get a fairly even round disk. Then I begin to actually roll it out flat. The round should be big enough, of course, to line the inside of your pie plate.

Roll the round of dough up with your rolling pin, the roll it out on top of a pie plate, which you will have greased well with a knob of lard or butter. (See Notes below about pie plate sizes). Using your fingers, make sure that the crust adheres to the sides. Cut off any excess dough that is hanging over the sides. (NB: A classic pastiera does not have any trimming around the edges.)

Pour the filling into the pie plate, taking care not to fill the pastry shell to the very top, since the filling will swell during baking.

Roll out the remaining 1/3 of the dough, then cut into strips. Lay the strips over the filling in a diamond-shaped (not square) lattice pattern. Press the strips gently into the shell and cut off any excess dough.

Place the pastiera in a moderate hot oven (190C/375F) for about an hour, until the filling is cooked through and the top has browned nicely. Check on it from time to time. If the pastiera is browning too quickly and looks like it might burn, you can cover it loosely with foil. If, on the other hand, an hour has passed and it's not a brown as you'd like, turn up the heat to 200C/400F and let it bake for another 15 minutes or so. (You can also run it under a broiler, but take care as the high-fat content in the pastry means it will burn easily if left unattended.)

Let the pastiera cool completely. If you have the time, let it rest overnight. Serve, straight from the pie plate, dusted with confectioner's sugar.