This recipe is used to fill Jacques Torres's Crepes.
Peel, core and cut the pears into 1/2-inch-thick slices and then cut in half crosswise.
Heat a large heavy-bottomed frying pan over medium-high heat. When the pan is warm, sprinkle the sugar into the pan in an even layer so it will caramelize at the same time. As soon as you see the sugar begin to melt, start moving the pan over the burner to keep the sugar from burning. Tilt the pan from side to side so that the melted sugar runs over the unmelted sugar. Cook until all of the sugar is a light golden brown. Add butter and cook until melted. Add pears and spread evenly in the pan. Pour in rum. Let cook over medium-high heat until most of the liquid has evaporated and the pears are soft but not mushy. They should hold their shape but the tip of a paring knife should easily pierce them. If the pears are still hard when most of the liquid has evaporated, add a few tablespoons of water and continue cooking until the pears are done. Pour the caramelized pears onto a plate.
To assemble the crepes, use a sharp paring knife to slice reserved vanilla pod halves into three strips lengthwise. If your vanilla bean halves are not wide enough to cut into three strips, just cut them in half lengthwise. These pieces will be used to tie the crepe bundles together. It is easiest to tie the bundles together if you have long, thin vanilla strips.
Place one crepe on a clean work surface. Fill the center of the crepe with about 2 tablespoons of the caramelized pears. Fold the crepe in half so that it looks like a fan. Bring the ends of the fan towards the center and tie the bundle with a vanilla bean strip. Make eleven more crepe bundles. If you don't have enough vanilla bean strips you can just fold the crepes closed. Stand the crepe bundles upright in the center of the plates and serve.