Preheat oven to 350°F (175°C). Line two baking sheets with parchment paper.
In a medium bowl, cream together the butter and sugar until light and fluffy. Beat in the eggs one at a time, followed by the vanilla extract.
In a separate bowl, whisk together the cocoa powder, baking soda, and salt. Gradually stir the dry ingredients into the wet ingredients until fully combined.
Scoop the dough onto the prepared baking sheets and bake for 10-12 minutes, or until the cookies are lightly browned around the edges. Allow to cool before serving.
Interesting Facts
Chocolate cookies were first created in the 1800s.
The key to chewy chocolate cookies is to not overbake them.
Adding a teaspoon of instant coffee to the dough can add a subtle flavor to the cookies.