Step 1:For the choux pastry, put the cider, salt and butter into a small saucepan and set over a low heat just until the butter melts, then increase the heat to high.Step 2:Once the liquid starts to boil, remove from the heat and quickly stir in the flour with a wooden spoon – you must do this vigorously and quickly to form a very thick, smooth dough. Put the pan back on the heat, stirring to dry out and smooth the dough – about a minute.Step 3:Put the dough into a mixer fitted with a paddle attachment. Beat the eggs in a bowl and add, a drop at a time, to the cooled dough, beating very well after each addition until it is completely incorporated. You may not need all of the egg; once the mixture is smooth and falls reluctantly from the spatula to form a V-shape, it’s ready.Step 4:Put the choux into the piping bag fitted with a large star nozzle.Step 5:Pipe the pastry into 7cm-diameter rings on the squares of baking paper.Step 6:Preheat the deep-fat fryer to 175°C. Place the pieces of baking paper, cruller-side down, into the oil, then remove the baking paper with kitchen tongs. Fry for a minute or two per side until golden brown and crispy. Remove with a slotted spoon and set onto kitchen paper to blot off the excess oil.Step 7:For the glaze, sift the icing sugar, then whisk in enough cider to make a thick icing. Dip the crullers into the icing and then dust with cinnamon and serve.