Directions
- Preheat oven to 300 degrees F.
- In a medium bowl, combine flour, baking powder, and salt with wire whisk. Set aside.
- In a large bowl, combine sugars using an electric mixer set at medium speed.
- Add butter and beat until batter is grainy.
- Add eggs, sour cream, and vanilla, and beat at medium speed until light and fluffy. Scrape bowl.
- Add the flour mixture, and blend at low speed until just combined. Do not overmix.
- Melt chocolate chips, using one of these two methods: a) Place chocolate chips in double boiler over hot but not boiling water. Stir constantly until melted. b) Place chocolate chips in a microwavable dish and heat on high, stirring every 20 seconds until melted.
- Cool chocolate for a few minutes and pour over cookie batter.
- Using a wooden spoon or rubber spatula, lightly fold melted chocolate in the dough. Do not mix chocolate completely into dough.
- Drop by rounded tablespoons, 2 inches apart, onto ungreased cookie sheets. (I always mold and flatten each cookie a little bit to make sure that each has a nice marble pattern.) Bake 20-22 minutes. Do not brown. Quickly transfer cookies to a cool surface.