Line a 9 inch (23cm) diameter springform cake pan/tin with parchment on the bottom (or you can leave if it's generally easy to unstick from).
Preheat the oven to 375F/190C.
Remove the chilled pastry, unwrap and cut off around ¼ of the dough. Re-wrap this small piece and place in the fridge while you work on the rest.
Roll out the larger piece of pastry on a lightly floured surface to form a large circle, then transfer the pastry to the cake pan/tin and gently press into the bottom and sides so that it evenly lines the base and most of the way up the sides. If needed, patch any thin areas or pieces where the pastry is lower. Trim it down a little below the top. Add the cut off scraps to the pastry that's chilling.
Place the drained ricotta, eggs, sugar, orange flower water and vanilla in a wide bowl. Whisk so everything is well mixed. Finely chop the candied peel and add this, along with the cooled grano cotto mixture, to the ricotta mixture. Stir so everything is well mixed.
Pour the ricotta filling mixture into the pastry in the cake pan - it should come to just a little below the top pastry level.
Remove the smaller piece of pastry from the fridge and roll it out into a strip that's about the length of the cake pan and half as wide, roughly. Cut long strips around ¾in (1 ¾cm) wide either with a knife or a pastry cutter - straight or wavy edges are both fine. Place the strips over the top of the cake/tart to give a cross design, usually three strips one way, four the other and with diamond-shaped spaces in between. Make sure the strips stick to the pastry around the side of the cake.
Carefully place the cake/tart in the oven and bake for around an hour. You may need to turn now and then to get even browning. If it browns too quickly, cover it for part of the time. When done, the cake should have a good relatively even light brown color over the top and no longer seem wobbly. It will likely puff up a little then deflate as it cools. If it's not quite brown or firm enough after the hour, give it a couple minutes more.
Leave the cake to cool completely then cover and chill overnight in the fridge to help the flavors mingle and for it to set a little better. Dust with powdered sugar, in particular on the pastry, before cutting slices and serving.