For the doughnuts, heat some of the milk, add yeast, then add some flour and sugar and mix everything together. Wait a few minutes until the yeast starts to rise.
Then add the egg and the yolk to the remaining milk, then add sugar and a pinch of salt. Add this mixture to the yeast.
Gradually add flour and mix everything until smooth. Cover and let stand for about half an hour.
Roll out the dough onto a floured surface to a thickness of about 1 cm and cut out the doughnuts with a mace. Do this until there is no more dough left.
Leave the doughnuts to stand for another half hour. (The longer you let them stand, the better). Heat the oil in a frying pan and place the doughnuts in it.
When they have cooled down a bit, sprinkle with powdered sugar.