Sweet potatoes and Yams.
Sea-salt and pepper
Chop the roots into wedges or cubes. Add to a baking dish and mix with un-toasted sesame oil - I normally roast at 425 degrees and the sesame oil can heat up higher without "turning" carcinogenic. If you want to use olive oil you have to baked them at max 350 degrees.
A dash of sea salt, fresh ground peppercorn and rosemary.
Half way through stir and add a little water to the bottom of the baking dish. It takes about 45 min in the oven to finish. Don't stir towards the end as you might make a mush.
Check the potatoes - it could be you like it more roasted so leave for another 10 min. Tasting is the way you figure that out.