Position a rack in the center of the oven and preheat to 325 degrees F. Wrap foil around the bottom of the springform pan. Bring a large pot of water to a boil and keep hot until needed. Spoon the ricotta into a mesh strainer over a large bowl until well strained.
Brush a little of the melted butter on the inside of the springform pan. Combine the graham cracker crumbs, remaining melted butter, 1/4 cup of the granulated sugar and 1/4 teaspoon salt. Firmly press the mixture into the pan, on the bottom and all the way up the sides. Bake until golden brown, about 15 minutes. Set the pan on a rack to cool. Raise the oven temperature to 350 degrees F.
Beat the ricotta, remaining 1 cup granulated sugar, vanilla, almond extract and orange zest in the bowl of a stand mixer on medium speed until combined. Add the eggs until just combined, taking care not to overwork the mixture. Pour the mixture into the cooled crust and place the springform pan in a deep roasting pan. Place the roasting pan on the center oven rack and carefully pour the hot water into the roasting pan until it reaches about halfway up the springform pan. Bake until just set and very lightly browned, for 1 hour and 35 minutes. The filling will appear puffed around the edges and should still be slightly jiggly in the center. Carefully remove the roasting pan from the oven and immediately transfer the cheesecake to a rack to cool completely. Refrigerate for at least 2 hours or overnight. Just before unlocking the springform ring, run a knife along the inside of the pan. Carefully lift the ring off.
Whisk the cream and confectioners’ sugar in a medium bowl until soft peaks form. Using a vegetable peeler, shave curls from the chocolate bar onto a plate and reserve for decorating.
At least thirty minutes before serving, run a knife along the inside of the pan to loosen the cheesecake and carefully lift the ring off. Allow it to sit at room temperature for at least 30 minutes. Spoon the whipped cream over the top and sprinkle with chocolate curls.
Cook’s Note: For the best texture and flavor, get the freshest and best ricotta you can find.