Heat oven to 375F.Combine flour,baking powder,baking soda,and salt in medium bowl.Set aside.
Combine butter, sugar and brown sugar in large bowl. Beat at medium speed, scraping bowl often, until creamy. Add eggs and vanilla. Continue beating, scraping bowl often, until well mixed. Reduce speed to low. Beat, gradually adding flour mixture, until well mixed. Stir in chocolate chunks.
Drop dough by 1/4 cupfuls, 2 inches apart, onto ungreased cookie sheets. Bake for 10 to 14 minutes or until light golden brown. (Do Not Overbake.) Let stand 1 minute on cookie sheets; remove to wire cooling rack.