1. For the filling: place the chopped chocolate in a bowl. Boil the cream in a saucepan, then pour over the chocolate gradually mixing until smooth. Let cool to room temperature.
. 2 Prepare the batter: In a large bowl, pour the flour, sugar and a pinch of salt. Make a well in center and pour in the milk and 15 ml water, crumbled yeast (or previously dissolved in a little warm water or milk) and eggs.
3. Mix with a spatula until it forms a ball of smooth dough. Knead for a few minutes it becomes soft and elastic, thenadd the butter . Cover with a clean cloth and let rise 1 hour 30 minutes at room temperature.
4. Place the dough on a lightly floured surface, flatten it with the palm of your hand and spread it gently with a rolling pin to a thickness of about 1 cm. Cut out circles with a cookie cutter 7 to 8 cm in diameter. Cover with a cloth and let rise 1 hour.
5. Dip the dough circles into a bath of hot frying three or four times depending on the size of the fryer. Turn over halfway through cooking. Drain on absorbent paper.
6. Fill the donuts drained chocolate using a pastry bag and sprinkle with sugar.