Make the dough:
Sift the flour, sugar, and salt together in a medium-size to large bowl. Using a pastry blender, a big serving fork, or the tips of your fingers, cut in or pinch or squeeze the shortening until the mixture resembles a bowl of sweet peas. Tossing the mixture quickly and lightly with a fork, sprinkle in the cream or milk 1 tablespoon at a time. (It's better to err on the side of not having enough liquid than to have too much; you don't want a soupy crust.) Continue tossing until the dough holds together when lightly pressed.
With lightly floured hands, loosely gather up the dough into a flat ball, place it in a bowl, and cover with plastic wrap. Refrigerate until you are ready to roll out the crust. I try to chill at least 30 minutes but not too much longer than overnight.
Roll out the dough and fill the pie:
Preheat the oven to 350°F.
On a lightly floured work surface, roll out the ball of dough into a 12-inch circle about 1/8 inch thick. Place a 9-inch pie plate upside down on top of the rolled-out dough. Using a small knife, cut around the plate, leaving a 1-inch border of dough around the plate. Remove the plate. Fold one side of the crust over in half. Fold the crust into quarters. Pick up the crust so that the center point is positioned in the center of the plate. Unfold the dough and press it firmly into the pie plate.
Trim all excess dough from the edge, except for a 1/2-inch flap of dough around the edge. Tuck the extra flap of dough under itself so it rests on the rim of the pie plate, and then crimp or flute the edge all the way around the pie.
Fill and bake the pie:
Crack the eggs into a large bowl and beat until well blended. Beat in the sugar, then stir in the ricotta and lemon juice and rind until thoroughly incorporated. Add the cream and stir until smooth and creamy. Fold in the rice, then stir in the cinnamon. Pour the filling into the pie crust. Place in the oven and bake until a toothpick inserted in the center comes out clean and the top is nicely browned, 45 to 60 minutes. Let cool completely on a wire rack before serving.
Photo: Alexandra Grablewski