Put the flour and salt into a large mixing bowl and rub in the butter, then add the sugar and yeast and mix until evenly distributed.
Add the eggs and milk.
Bring the mixture together into a ball and tip out onto the worktop.
Knead the dough until smooth – it will be very soft and sticky to begin with, but persevere; it should be smooth in around 10 minutes.
Place the dough back into the bowl and leave to rest, covered with a tea towel at room temperature until doubled in size, at least one hour.
Once the dough has doubled in size, scrape it out of the bowl onto a lightly floured surface and using your hands, pat out the dough into a rough rectangle before rolling the dough out to around ¼ inch thick.
Cut the dough using a sharp knife or a pizza cutter into diamonds/squares and leave to rest for around 10 minutes, while the oil heats.
To cook the beignets, fill a wide saucepan with the oil and heat to around 170˚C.
Carefully pick up the doughnuts and place in the oil to colour on one side until golden brown, then flip the doughnuts and cook on the other side.
This should take around 2-3 minutes.
Once cooked, drain the doughnuts on some kitchen roll and liberally cover with icing sugar.
Serve hot with the blueberry sauce.
To make the blueberry sauce, place all the ingredients apart from the cornflour in a saucepan over a medium flame, and gently heat for around 5-8 minutes.
Mix up a paste with the cornflour and water and add to the saucepan, stirring continuously until you have a thickened sauce.
Serve immediately, or keep covered and gently re-heat before serving.
