Sift flour, baking power,baking soda and salt into a bowl. Set aside.
Beat butter and suger together with a mixer until very light, about 5 minutes. Add eggs, one at a time, mixing well after each addition. Add vanilla. Reduce speed to low. Add flour mixture and mix just until combined, 5 to 10 seconds. Stir in candy bits.
Drop dough by tablespoons onto baking sheet. Bake 15 to 20 minutes. Cool on baking sheet 2 minutes. Transfer to wire rack to cool completely. Makes about 4 dozen cookies.