4 1/4 cups all-purpose flour
1 teaspoon baking powder
1 teaspoon baking soda
1/2 teaspoon salt
1 1/2 cups unsalted butter
1 1/4 cups sugar
1 1/4 cups firmly packed brown sugar
1 tablespoon vanilla
1 (12-ounce) package (2 cups) semi-sweet chocolate chunks or chocolate chips
1 cup chopped nuts (optional)
Heat oven to 375°F.
Combine flour, baking powder and baking soda in a medium bowl. Set aside.
Combine butter, sugar and brown sugar in a large bowl. Beat at medium speed, scraping the 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 and nuts (optional).
Drop dough by 1/4 cupfuls, 2 inches apart, onto ungreased cookie sheets (tip: line the sheets with parchment, if you have some). Bake for 10 to 14 minutes or until light golden brown. (Do not overbake.) Let stand 1 to 2 minutes. Remove from cookie sheets.