Peel and core the apples, and cut the flesh into fairly small dice. Add to a small saucepan with the lemon juice, sugar, spices and chopped prunes (or raisins) and cook for around 5 minutes over a medium heat, until fairly soft.
Meanwhile, lay out a sheet of filo pastry on a slightly damp, clean tea towel (my pastry sheets each measured around 12 x 16 inches). Spray the pastry lightly with oil, and place another sheet on top. Repeat until you've used all of the pastry - I used 7 sheets in total.
In a small bowl, combine the cottage cheese and egg, and mix well.
Spread the cottage cheese mixture over one half of the filo pastry, and top with the apple mixture. Starting from one of the short ends of the rectangle (choose the end that you covered with filling - see picture above), tightly roll the pastry. Wrap the pastry roll tightly in the tea towel, and tie the ends with string.
Place the roll in a large pan of water, and bring to a boil. Cook for around 30 minutes, then drain. When the roll is cool enough to handle, cut the string, and unwrap the tea towel. Cut the štruklji into slices, and serve topped with a sprinkle of icing sugar.