To drain the ricotta, place it in a fine-mesh strainer lined with a large double-layer piece of cheesecloth. Place the strainer over a large bowl. Wrap the ricotta tightly in the cloth, squeezing to start extracting liquid. Place a heavy bowl on top and refrigerate for at least one hour. (You can start making the pastry dough while the ricotta drains if you like.)
Discard the liquid and transfer the ricotta to a large bowl. Add the mascarpone, sugar, and vanilla. Beat with an electric mixer on medium speed for about 2 minutes, until smooth and slightly fluffy. On low speed, mix in the cinnamon, nutmeg, allspice, ginger, and pumpkin. Refrigerate the mixture at least 30 minutes, or until ready to serve.
Meanwhile, make the pastries. Whisk together the flour, sugar, baking soda, cornstarch, cocoa powder, cinnamon, and salt in a large bowl. With the whisk, work in the shortening to create a crumbled texture. In a separate small bowl, combine the vanilla extract, vinegar, and bourbon, then stir the liquids into the flour mixture. Add cold water a teaspoon at a time as needed to create a cohesive dough. Knead about 2 minutes, until smooth.
Divide the dough in half. In between sheets of wax paper, roll each half into a circle about 1/8-inch-thick. Let stand covered at room temperature for about 20 minutes.
When ready to cook, start heating about 1½ inches of oil to 365°F in a heavy, deep-sided pan over medium heat.
Working with one piece of dough at a time, roll the dough to about 1/16-inch thick. Use a 3-inch cutter to cut circles, rerolling scraps. The dough will tend to contract, so right before frying, roll over the circles with the rolling pin to thin them (it’s okay if they end up as ovals or odd shapes—that’s part of the rustic charm). You should end up with 20 to 24 rounds.
Fry the rounds in small batches to avoid crowding the pan, turning a few times, until brown, 1 to 2 minutes. Transfer to a paper-towel-lined plate to drain and cool completely.
Make the sugar topping by combining the confectioners’ sugar and cinnamon.
To serve, place one pastry round on a serving dish and top with a generous dollop (3 to 4 tablespoons) of pumpkin ricotta filling. Top with another pastry piece, and finish with a dab of whipped cream (if using) or more pumpkin filling. Generously dust the tops with the sugar-cinnamon mixture. Serve immediately.