Preparation

1. Position 2 oven racks in the middle and upper third of the oven. Preheat the oven to 177°C (350° F). Line two baking sheets with heavy aluminum foil, sprayed with cooking spray. Sift the flour, baking powder and salt together and set aside. Put butter, brown sugar and granulated sugar in the large bowl of an electric mixer and beat on medium speed for about one minute, until the mixture is smooth. Add the egg and vanilla and mix on low speed for about 15 seconds until they are blended thoroughly. Scrape bowl. Decrease speed to slow and gradually add the flour mixture, mixing just until incorporated. Mix in the chocolate chips.

2. Using a small cookie scoop, approximately 3 cm (1¾ inch) diameter, place dough about 6.5 cm (2½ inches) apart on the prepared cookie sheets. Bake the cookies until the centers are golden and the edges are light brown, 13-15 minutes. Reverse the baking sheets after 7 minutes, front to back and top to bottom, to ensure even browning.When done, the center of the cookie should feel slightly firm, not soft, when lightly touched. Cool the cookies for a few minutes on the pans then transfer to cooling racks. Wrinkled tops indicate an excellent cookie!