Preheat oven to 350 degrees.
In a small microwave safe bowl, add butter and semi-sweet chocolate (cubed/broken up) and microwave for 45 seconds to 1 minute (on the lowest power level), stirring twice. The goal is to melt the butter and chocolate, not to cook it at all!
Using a kitchen aid stand mixer on the lowest speed (using the paddle attachment), combine melted butter/chocolate with brown and white sugar. (Use a regular beater in place of a stand mixer.)
Add in the vanilla and two eggs and increase speed to medium high. Beat until light and fluffy -- approximately 8-10 minutes (see photo number 3).
Meanwhile, in a large mixing bowl, sift together flour, coco, baking powder and salt.
Once the butter/sugar/egg mixture is fluffy, carefully add in (on low speed!) the flour mixture. Mix until combined.
Remove the mixing bowl from the stand and with a wooden spoon, fold in chipits.
Roll tablespoon sized balls and place on parchment lined baking sheets two inches apart. Give them all a good press down to flatten slightly.
Bake at 350 for 15 minutes (a little less or a little more, depending on the size you make them). Enjoy!