This little trick comes from Big Bob Gibson's BBQ Book by Chris Lilly. It is so easy and effective that it is ridiculous. You simply roast sweet potatoes on a bed of coals. No oil. No rub. No foil.
I had just finished smoking a turkey breast and put 4 sweet potatoes in the coals.
20 minutes on one side.
Flip and 20 minutes on the other side.
Don't worry if they look, smell, or otherwise seem that they are burning. The sweet potato shells may even be fragile and break when you remove them. It's okay.
As they are cooling melt 1/4 cup butter and mix in 1/4 cup maple syrup, 1/8th teaspoon each of cayenne pepper, cinnamon, and salt. Chris Lilly also adds pecans to his mix but pecans represent all that is evil in the world so I skipped them. Split the sweet potatoes and drizzle the butter mixture over them.
These were so tender that they just melted under the fork as it drove down into them. The sauce poured buttery-sweet-spicy flavor all over the potatoes.
This is a great technique for cooking sweet potatoes if you ever need cooked sweet potatoes in a dish. But adding the sauce topping makes them shine as a side dish.
It's dishes like these that make Chris' book one of my favorite live fire cook books.