Preheat oven to 400 degrees.Line a rimmed baking sheet with parchment paper. Rub parchment paper with a bit of coconut oil.Wash and scrub sweet potatoes, and cut them in half lengthwise. Sweet potatoes can be difficult to cut in half, so make sure to use a sharp chefs knife.Generously rub both sides of each sweet potato with the melted coconut oil and then sprinkle with sea salt. Tip: If you don't want to melt your coconut oil in the microwave, you can use a small oven-proof bowl or ramekin and melt the coconut oil in the oven while it's preheating. This only takes a few minutes.Place the sweet potatoes cut-side down on the parchment paper. Sprinkle tops of sweet potatoes with additional salt.Roast them in the pre-heated oven for about 25-30 minutes (roasting times can vary, as sweet potatoes vary in size).The best way to tell if a sweet potato is finished cooking is to use your hands. They're finished when you can easily squeeze them, and the skins will dent when poked with a finger, also the skin should easily pull away from the potato. Flip them over and the interiors will be soft, and the edges slightly browned and caramelized.These sweet potatoes are best served warm.Slather each sweet potato with some coconut oil or butter and additional sea salt to taste. The coconut oil and butter will melt into the sweet potato and it will glisten and beckon for you to dig in.