Prepare a large baking sheet with parchment paper and set aside.
In a small bowl mix the chopped apple, sugar, and cinnamon until the apples are fully coated, then set aside until use.
In a large bowl, whisk together the flour, sugars, baking powder, cinnamon, nutmeg, and salt.
With a pastry cutter or fork, cut the cold butter into the flour mixture until almost fully incorporated, then mix in the apples.
In a separate bowl, whisk together the apple cider, egg, and vanilla extract.
Pour the wet ingredients over the dry, mixing until just barely combined. The mixture should be rough at this stage.
Move the dough to a floured surface and gently knead the dough into a rough ball. If the dough is too wet, add small handfuls of flour until it's dry enough to be handled and shaped.
Form the dough into a flattened disc (about 7-8 inches wide) and cut 8 equal wedges, placing them slightly apart on your prepared baking sheet.
Chill the scones in the fridge while you preheat your oven to 400ºF.
Whisk the egg and milk/water together in a small bowl, then brush the egg wash over the tops of each scone with a pastry brush. Sprinkle with cinnamon sugar before baking if desired.
Bake for about 20 minutes or until golden brown and risen.
While the scones cool slightly, whisk together the apple cider and powdered sugar for the glaze. Drizzle over the top of your scones before serving.