The story begins with a small family in a cabin in the woods.  Each night, they hear a knock at the door, and whoever answers the door disappears.  The reader soon discovers that the a pair of magic boots have been walking themselves up to the door, forcing themselves onto the feet of who answers, and walking them off into the forest.  Each family member disappears until only 1 boy, the protagonist, is left.  He manages to trap the boots in a pot, pours (honey or molasses?) onto the boots, and puts 2 rats into the enclosure with the boots.  The rats eat the boots and become "bewitched," and the boy stands on the rats and rides them into the forest to find his family.  He is led to a troll or giant, but I cannot remember how the story concludes.