Combine ginger powder, ground cinnamon, sugar and nutmeg in a small bowl. Stir to mix well. Leave aside.
Sift both flours into a mixing bowl. Stir in salt, sugar and yeast.
Combine milk, lukewarm water, egg and butter in a jug. Pour this mixture into the flour. Knead using an electric mixer fitted with a dough hook until a soft dough is formed.
Turn out dough onto a lightly floured tabletop and knead by hand until smooth. Cover the dough with a damp tea towel. Leave to proof for 1 hour or until well risen or doubled in size.
Sprinkle a little flour over and knead again for a minute or two until smooth. Roll out dough to a 1cm thick rectangle. Sprinkle liberally with combined ginger sugar. Fold over the rectangle into half. Roll out lightly (do not press). Cut out into equal small squares.
Using a sharp knife make 8 shallow cuts from the edge to the centre of square (to form a windmill). Cut out a small portion leaving a hole in the centre. Place the squares on a baking tray lined with nonstick baking paper. Leave aside for 30 minutes or until well risen.
Heat oil in a wok over medium heat. Deep-fry the doughnuts in batches until golden. Remove doughnuts after frying and drain on absorbent paper. Coat the doughnuts with the combined ginger sugar.