Preheat oven to 350. Peel off the first outer layer of the corn husk and discard. Rinse outsides well or submerge in a bowl of water to wet, allow excess to drain off and set on a baking sheet in a single layer.
Bake in husks for 40 minutes, turning corn hallway through baking. Remove from oven and let stand 10 minutes.
Use a sharp knife to cut the ends off both sides (1.5" or so). Pull back husks, butter and salt before serving.