1 1/3 cups all-purpose flour

1/2 tsp baking soda

1/2 tsp salt

10 tbsp (1 1/4 stick) unsalted butter,softened

3/4 cup light brown sugar.firmly packed

1 tsp vanilla extract

1 large egg

6 ounces bittersweet (not unsweetened) chocolate,cut into 1/4-inch pieces

6 ounces milk chocolate, cut into 1/4 inch pieces

2 cookie sheets lined with parchment

After you cut up the chocolate, place it in strainer with fairly wide mesh and sift away the dust formed buy cutting it- the cookies will have a neater appearance.

1.Set racks in the upper and lower thirds of the oven and preheat to 350 F

2.Stir the flour,baking soda, and salt together and set aside.

3. Combine the butter, brown sugar, and vanilla in the bowl of an electric mixer. Beat with the paddle on medium speed until just mixed, then beat in the egg. (Overbeating this type of cookie dough will make this cookie rise, then flatten out during cooking, instead of remaining risen and moist.)

4. Remove the bowl from the mixer and use a large spatula to stir in the flour mixture, then the chocolate.

5. Drop the tsp of the dough 2 to 3 inches apart on the prepared pans to allow for spreading. Bake the cookies until they are spread, well risen, and golden, about 15 minutes. About halfway through the baking, place the pan from the lower rack on the upper one and vice versa, turning the pans back to front at the same time.If you that your oven gives strong bottom heat, place the pan on the lower rack stacked on top of a second one for insulation.

6. Slide the parchment papers off the pans to cool the cookies.