To make the shortcakes:
- In a medium-sized bowl, whisk together flour, sugar, baking powder, baking soda, and salt. Add diced shortening. Using your clean hands or a pastry cutter, mix the butter into the flour mixture until the mixture is the consistency of coarse meal with small pea-sized pieces throughout.
- In a small bowl or measuring cup, whisk together the egg and buttermilk. Using a rubber spatula, mix in the buttermilk mixture until a shaggy dough just comes together.
- Preheat oven to 425°F and line a baking pan with parchment.
- Turn biscuit dough out onto a lightly floured surface and roll out until dough is about ½-inch thick. Fold the dough in thirds, letter style, and roll into a 9″ x 6″ rectangle. Using a lightly floured knife or bench scraper, cut the dough into 8 pieces.
- Transfer biscuits to the prepared baking sheet and arrange in two rows of four, leaving about an inch between them. Brush the top of each biscuit with cream and sprinkle with cinnamon and granulated sugar, if desired.
- Bake biscuits for 10 minutes, or until tops are lightly golden brown. Let biscuits cool completely before assembling shortcakes.
- Shortcakes can be made a day in advance and stored in an air-tight container at room temperature.
To make the apple pie filling:
- In a large saucepan, combine apples, sugar, maple syrup, and ground cinnamon, stirring until apples are evenly coated. Cook over medium heat until apples are slightly tender, 3 to 5 minutes.
- Stir together water and corn starch; add to the saucepan. Stir constantly, until mixture thickens, and then cook over medium low for 10 minutes.
- Remove from heat and stir in vanilla. Let the filling cool for about 20 minutes, or until just slightly warm.
To make the whipped cream:
- Combine heavy cream, powdered sugar, and vanilla in a medium-sized bowl or the bowl of a stand mixer fitted with the whisk attachment. Whip on medium high speed until stiff peaks form.
- Whipped cream is best when made the same day you plan to serve the shortcakes. If storing in the refrigerator until ready to use, give the whipped cream a quick whisk before using.
- To assemble the shortcakes, cut each biscuit in half. Layer apple pie filling and whipped cream on each shortcake base and add the shortcake tops. Top with additional whipped cream and filling if desired.
- Shortcakes are best the day they’re assembled.