Warm the milk: Heat the sugar and milk in a pan for about 5 minutes until warm and the sugar dissolves. Crumble the yeast into a bowl, pour in half the warm milk, mix and set aside.
Add the butter: Place the remaining milk back on the heat and add the butter. Heat gently for 3 minutes without letting it boil.
Make the dough: Sift the flour and salt into a large bowl. Add the egg yolks, yeasted milk and hot buttered milk. Mix together to make a dough.
Knead and rise: Tip onto a floured surface and knead until smooth and elastic. Place in a floured bowl, cover with cling film and leave to rise for 1 to 1.5 hours until doubled in size.
Shape: Knock back the dough and roll out to 2cm thick. Cut into 12 rectangular pillows. Place on lined baking paper and leave to rise again for 30-40 minutes.
Make the ganache: Heat the cream with honey until almost boiling. Pour over the chopped chocolate and butter in a bowl. Stir until smooth and glossy.
Fry: Heat oil to 170°C. Fry the doughnuts in batches for 3-4 minutes until evenly golden brown. Remove with a slotted spoon and roll in malt sugar to coat.
Fill and serve: Spoon warm ganache into a piping bag with a small nozzle. Insert into each doughnut and gently squeeze in the filling. Serve straight away.
