These double chocolate chip cookies are everything you want in a sweet treat-rich, gooey, and bursting with chocolate.
Preheat your oven to 350°F. Optional to line your baking sheets with parchment paper for easy cleanup.
In a large mixing bowl with the paddle attachment, cream together 1/2 cup each of butter, granulated sugar, and brown sugar on medium speed until light and fluffy, about 2-3 minutes
Beat in 1 egg, then stir in 1 teaspoon of vanilla extract scraping the bowl as needed.
In a separate bowl, whisk together 1 cup of flour, 1/3 cup of cocoa powder, 1/2 tablespoon of cornstarch, 1/2 teaspoon of baking soda, and 1/4 teaspoon of salt. Gradually mix the dry ingredients into the wet ingredients until just combined.
Fold in 1 cup of chocolate chips, reserving a few to press onto the tops of the cookies (for esthetics only). You can bake right away but you may want to refrigerate for atleast an hour to help cookies retain their shape. Just allow to sit at room temperature for 10 minutes before scooping to make it easier to scoop. If refrigerated for longer than 3 hours, the dough may need 20 minutes to sit at room temperature first.
Scoop dough onto the prepared baking sheets using a cookie scoop (I used a medium baking scoop of about 1 and 1/2 tablespoons), spacing them about 2 inches apart.
Bake for about 8-12 minutes, until the edges are set but the centers still look slightly soft.
Allow the cookies to cool on the baking sheet for 5 minutes before transferring them to a wire rack to cool completely.
Store covered at room temperature for up to 1 week. You can make the cookie dough and chill in the fridge for up to 3 days before baking. Unbaked cookie dough balls can be placed in the freezer for up to 3 months. Thaw for 20 minutes before baking as per instructions. Baked cookies can be frozen for up to 3 months in a freezer-safe bag or container.