Preheat oven to 350°F and spray a 9 X 9" baking dish or slightly larger with cooking spray.

In a bowl mix together the graduated sugar, yogurt, and vanilla extract until combined.

To the mixture add both eggs one at a time, mixing well after each, until thoroughly mixed.

Sift together the flour, salt, and cocoa and add to the mixture, when done add the chocolate chips and spread evenly into the prepared baking dish.

Bake in the preheated oven for 25-30 minutes or until an inserted toothpick comes out clean.

Let cool completely (then sift some confectioners sugar over the top, optional) and cut however you'd like.