You can absolutely use confectioners sugar (also known as powdered sugar or icing sugar) here and I have made ladoos using that in the past. But, now I almost always use bura because it gives the ladoos a nice texture when you bite into it. You don't get the same texture with confectioners sugar/icing sugar as it has added cornstarch to it. The texture of bura is different and the taste is also superior which will make your ladoos tastier.