Preheat oven to 350 degrees F.
With a mixer, cream the butter and sugar til well combined and fluffy (about 3-4 minutes).
Add in the vanilla and egg and mix again to combine.
In a seperate bowl, whisk together flour, baking soda, salt, coffee and cocoa powder.
Slowly start to add in your dry ingredients into the wet ingredients bowl.
Once everything is well combined together, portion out the cookies and place them on a parchment lined baking sheet.
Bake for 8 minutes or until the edges are firm and allow them to cook completely on a wire rack.
Microwave the Nutella in 20 second increments until it is smooth to spread on top.
Take a cooled cookie and spread a thin layer of nutela on top. Repeat for each cookie.
Dust with icing sugar on top and enjoy!