Preheat oven to 350 degrees F. Line two baking sheets with parchment paper, set aside.

To make the cookies: In a a large bowl, cream together the butter and sugar until light and fluffy, about 3 to 5 minutes on high. Add the eggs, one at a time, mixing well after each addition. Stir in the vanilla extract.

In a separate bowl, combine the flour, cocoa, baking soda and salt. Add the dry ingredients to the creamed butter and stir until just incorporated. Scoop out 24 even dough mounds onto the prepared baking sheets. Bake for about 7 to 8 minutes or until the cookies are set, do not over bake. Remove from oven and allow to cool down for a few minutes on the baking sheets. Transfer to wire racks to cool completely.

To make the frosting: In a large bowl, cream together all of the ingredients until fluffy, about 5 to 7 minutes, on high. Sandwich the cooled cookies together with about 2 tablespoons or so of frosting in the middle. Place in the fridge to set for a few minutes before eating. Enjoy!