Add the apple cider to a saucepan and bring to a boil, keep on a rolling boil until it has reduced to about 4 tbsp (it will be thick and sticky). Set aside.
Preheat the oven to 350℉/170℃. Line 2 large baking sheets.
In a large bowl, or the bowl of a stand mixer, cream together the butter and both sugars. Use an electric mixer - everything should look fluffy, pale and fully combined.
Add the egg and reduced apple cider and whisk again.
Add the flour, baking soda, cream of tarter, ginger and cinnamon. Mix until fully combined.
In a separate bowl, combine the coating ingredients (the sugar and spices).
Using a tablespoon/tbsp size cookie scoop, scoop a ball of dough. Roll with your hands into a ball, then coat in the sugar mix. Place on a prepared baking sheet - place cookies at least 2 inches apart. Repeat to use up all dough (you may need to work in batches).
Bake 10-12 minutes, until golden and crinkled on top. Remove and let cool before serving!