Roll out puff pastry into a rectangle, about 12 by 15 inches. Spread preserves over the dough, to within 1/2-inch 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 1/2-inch 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 minutes, until puffed up and golden brown.
Scoop frozen yogurt or ice cream into dessert bowls and lay twists over top.