<p style="text-align: justify; ">In the bowl of a mixer fitted with a paddle attachment, beat the softened butter with the two sugars for 2 minutes, until you obtain a creamy mixture.</p><p style="text-align: justify; ">Add the egg and mix well. Then, gradually add the flour and baking powder while continuing to beat, until the dough is smooth.</p><p style="text-align: justify; ">Finish by incorporating the chocolate pieces.</p><p style="text-align: justify; ">Cover the dough and place it in the refrigerator for at least 1 hour.</p><p style="text-align: justify; ">&nbsp;Form balls of dough of about 30 g each and place them on a baking sheet lined with parchment paper.</p><p style="text-align: justify; "><br></p>