1) Preheat the oven to 200C/Gas 6.
2) Roll out puff pastry into a rectangle, about 30 by 38cm. Spread preserves over the dough, to within 1cm of the edges. Fold dough in half lengthwise. Gently roll again to seal edges. Using a sharp knife or pizza cutter, cut dough crosswise into 1cm thick strips. Take each strip by the ends and tie into a knot. Arrange knots on a large baking sheet and press down the ends. Bake 6 to 10 mins, until puffed up and golden brown.
3) Scoop frozen yoghurt or ice cream into dessert bowls and lay twists over top.