Step 1

Preheat the oven to 350°F and line baking sheets with parchment paper.

Step 2

In a large bowl, cream together the butter, granulated sugar, and brown sugar until smooth. Beat in the egg and vanilla extract.

Step 3

In a separate bowl, combine the flour, black cocoa powder, corn starch, baking soda, and salt.

Step 4

Gradually add the dry ingredients to the wet ingredients and mix until well combined. Fold in the chocolate chips.

Step 5

Scoop about 2 tablespoon of dough onto the prepared baking sheets and bake for 8 to 10 minutes in the preheated oven, or until set.

Step 6

Allow cookies to cool on baking sheet for 5 minutes before transferring to a wire rack to cool completely.