Chocolate Ginger Snap sandwiches with Nutella filling

This recipe is MINE.  All mine.  Combining things I love into a decadent holiday cookie that can't be beat. It is by far the most elaborate cookie I make, but worth it.

If there is one secret to this cookie, it is letting it sit for at least a day in an airtight container with the Nutella inside to let the cookies get soft again.
Unbeatable!

Recipe - Chocolate Ginger Snap sandwiches with Nutella filling

Equipment:
stand mixer/hand mixer & bowl
3-4 C bowl
rubber spatula
regular spoon
baking sheet (+silpat)
cooling racks
butter knife
airtight container(s)

Ingredients:
3/4 C (1.5 sticks/ 6oz.) butter
1/4 C brown sugar
1/2 C granulated sugar
1 egg yolk (if you use the whole egg it'll work, just need to cook longer)
1 tsp vanilla
1/2 C molasses

1 3/4 C flour
1/2 C cocoa powder
1 tsp baking soda
1/2 tsp ground black pepper
2 tsp ground ginger
1/2 tsp allspice
pinch of salt (if using unsalted butter)

1/2 C chopped candied ginger (Trader Joe's or an Asian grocery - crystalized ginger will work in a pinch)

Nutella

Prep:
In a 3-4 C bowl, stir together the flour, cocoa powder, baking soda and all the dry spices (pepper, ginger, allspice, salt).  Set aside.
In the stand mixer, beat the butter until smooth.  Beat in the sugar until the mixture has a fluffy texture.  Add in the egg yolk, vanilla and molasses.  Scrape down the sides of the bowl and make sure everything is combined.
At low speed, slowly add in the flour mixture.  When everything is combined, put in the chopped candied ginger, and stir until just mixed in.

Scrape the dough into the bowl you used to mix the flour.  Pop it in the fridge for at least 30 min. (Overnight is fine!)

Cook:
Preheat the oven to 375˚F.
Use the spoon to scoop out dough and roll it into 1 inch balls.  Place them 2 inches apart on your baking sheet (silpat).  When the pan is full, lightly press down on the dough to slightly flatten each one.

Bake for about 10-12 minutes.

Let the cookies cool until they start to get solid.  Move them to a cooling rack.
Match up cookies by size.  Spread one cookie with a layer of Nutella, and make the sandwich.  Place in an airtight container for at least a day.  The cookie with soften, and make a decadent treat.

You can of course taste a few while still crispy for comparison.