In a medium bowl, whisk together flour, baking powder, salt and spices.
In the bowl of a stand mixer with the paddle attachment, cream the butter and sugar together until light and fluffy. Add the egg and extracts and mix until completely combined.
Add the flour mixture all at once. Mix at a low speed until combined. Form into a disc and wrap in plastic, chill for at least 1 hour.
Preheat the oven to 350°F/175°C. Line 2 baking trays with parchment paper. Roll out the chilled cookie dough on a floured work surface until ½" thick. Cut the dough using cookie cutters. I cut out 18 plain circles and 18 circles punched out with an autumn shape. Transfer the cookie to a baking sheet and chill in fridge for 15 minutes
Bake for 10-12 minutes until golden around the edges. Cool completely.
Chocolate Frosting
In the bowl of a stand mixer with the whisk attachment, beat the butter until light and and creamy.
Add the cocoa powder and beat on low speed until completely combined.
Add the icing sugar, vanilla extract and 2 tablespoons of milk. Beat on a low speed and increase to high, beating until light and fluffy. Add another tablespoon if the frosting seems too stiff.
Assembly
Take the cooled plain circles and using a small offset spatula, spread chocolate frosting on the cookie. Top with another circle. If you wish you can sprinkle some sugar or cinnamon sugar on top!