In an oven-proof dish (preferable a Dutch oven), add the entire box of salt. Bake at 450 degrees for 1 hour.
After one hour, remove the pan from the oven and carefully pour out approximately two-thirds of the salt into another oven-safe dish and set aside. (Note: The salt is extremely hot. Use caution!)
Insert a wooden skewer into each pear. Position each pear on top of the salt remaining in the pan. Don't let the pears touch one another. Pour the reserved salt on top of the pears, covering them completely. Return to the oven and bake another 15 minutes.
Remove pan from the oven and carefully pour out the salt. (Remember, the salt is extremely hot!) Brush away any clinging salt from the pears and set them on a plate to cool.
Cut off the tops of the pears and core out the centers, leaving the bottoms intact.