Put a chopping knife in the bowl of the combine, pour two types of flour, salt, baking powder and cut butter (cold) into pieces on top. Whisk the mixture into a homogeneous crumb, it will take only 30 seconds. Add vanilla and plain sugar to the flour crumbs and stir the mixture for another 30 seconds. Without stopping the combine, add the egg to the flour mixture, let the egg stir for 20-30 seconds, if the dough remains in the form of crumbs, add cold water through the hole in the lid (1 spoon each).