Instructions

1. Preheat oven to 350 degrees F. Lightly grease a cookie sheet or line it with parchment paper.
2. In a large bowl, using a hand or stand mixer, cream the butter until smooth. Add in the brown sugar, granulated sugar, egg, and vanilla and mix until just combined. Add in the flour, baking soda, and salt and mix until a soft dough has formed. Stir in the chocolate chips.
3. Drop the dough by tablespoon, or use a cookie scoop, 2 inches apart onto a cookie sheet. Bake for 10-12 minutes until the edges start to turn golden brown. Allow the cookies to cool on the cookie sheet for 5 minutes before moving them to a cooling rack.
4. Prepare the frosting. In a small microwavable safe bowl, heat the butter and chocolate in the microwave for 30 seconds. Stir, cook again for another 15 seconds. Continue heating the chocolate for 15 seconds at a time, stirring in between, until completely melted.
5. Mix in the powdered sugar, vanilla extract, and the coffee (or cream) until smooth. If the frosting is too thin, add more powdered sugar. If the frosting is too thick, add more liquid.
6. Spread 1 teaspoon of chocolate frosting on one side of a cookie and top with remaining cookies.
7. Store covered at room temperature or in the fridge.