Baked sweet potato skin hard as a rock I tried to bake a sweet potato today, but instead of getting soft, the skin kept getting tougher and tougher. Eventually i took it out and when I cut into it, the inside was soft, but the shell outside was really tough (yes, it did feel like a shell)

Any ideas? These were my steps:


Pre heated the oven for 10 mins at about 212 F
Put the potato inside, skin on, on a rack with aluminium foil at the bottom
Let it bake at 300 F for 40 mins.
Shell super hard, fork couldnt go through, so put it back in for another 40 mins.
Shell even harder.  Turned up temperature to 400 F.
About 20 mins later i smell a little burning so i took it out. The shell was just a little burnt on the outside but still really tough.


I guesa this could be because i didnt use oil. I dont want to use oil. Any ideas?
It could be that your oven temp is too low during the cook, so you are essentially dehydrating the outside of the potato.  I would preheat to 350 for at least 30 minutes, to make sure your oven is up to temperature.  Then put the potatoes in.