How do you make your baked potato skins crispy?

I accidentally made one part of my potato super crispy the other day (I didn’t rub the oil/salt around and it got really hard and crispy) and it was AMAZING. I haven’t been able to duplicate that.

I’ve looked online but the answers weren’t that helpful. I’m trying to make these potatoes as healthy as possible.

Any tips?

Also, while we’re on the topic, what are your favorite toppings? I like fat free sour cream, fresh chives, a little fake butter and hot sauce