Step 1

Preheat oven to 350 degrees F.

Step 2

Cream together butter and sugar until fluffy in a stand mixer on medium-low speed or by hand.

Step 3

Add egg and vanilla, and continue mixing until smooth.

Step 4

In a medium bowl, stir together flour, cocoa powder, baking soda, and salt. Add dry ingredients to butter mixture, and mix on low speed (or stir) until combined. Dough will be very stiff.

Step 5

Add chocolate chunks, and stir to incorporate.

Step 6

Line two baking sheets with silicone mats or parchment paper. Use a large cookie scoop to place cookies about 2" apart on prepared baking sheets. Bake for 12 minutes, or until centers are set.

Step 7

Cool for a few minutes on the pan, then transfer to wire rack to cool completely.